Prometrium

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Prometrium

Classes

Compounding Kits, Hormonal Agents
Other Infertility Agents

Administration

Hazardous Drugs Classification
NIOSH 2016 List: Group 2
NIOSH (Draft) 2020 List: Table 2
Observe and exercise appropriate precautions for handling, preparation, administration, and disposal of hazardous drugs.
INJECTABLES: Use double chemotherapy gloves and a protective gown. Prepare in a biological safety cabinet or compounding aseptic containment isolator with a closed system drug transfer device. Eye/face and respiratory protection may be needed during preparation and administration.
ORAL TABLETS/CAPSULES/ORAL LIQUID: Use gloves to handle. Cutting, crushing, or otherwise manipulating tablets/capsules will increase exposure and require additional protective equipment. Oral liquid drugs require double chemotherapy gloves and protective gown; may require eye/face protection.
TOPICAL/TRANSDERMAL/VAGINAL: Use double chemotherapy gloves and protective gown. Eye/face and respiratory protection may be needed during preparation and administration.

Oral Administration

Administer progesterone with or without food; evening dosing is suggested.

Injectable Administration

Visually inspect parenteral products for particulate matter and discoloration prior to administration whenever solution and container permit.

Intramuscular Administration

Administer intramuscularly. Never administer intravenously.
Shake vial thoroughly prior to withdrawing dose into the syringe.
 
Intramuscular injection:
Injections cause irritation at the injection site.
Inject deeply into a large muscle mass. Rotate sites of injection.

Intravaginal Administration

Intravaginal gel (Crinone, Prochieve):
Use disposable applicators supplied by the manufacturer.
Instruct patient on proper administration. The Patient Information Sheet contains special instructions for using the applicator at altitudes above 2500 feet in order to avoid a partial release of the gel before vaginal insertion.
 
Intravaginal suppositories (Endometrin):
Use disposable applicators supplied by the manufacturer.
Patients should be instructed to place the thin end of the applicator filled with the insert well into the vagina while standing, sitting, or lying on her back with her knees bent. The plunger on the applicator should be pushed to release the insert. Discard the applicator after each use.

Extemporaneous Compounding-Vaginal

Extemporaneous Intravaginal Suppositories preparation:
One compounding formula that has been used is as follows:
710 mg (0.71 grams) progesterone powder
33.7 grams polyethylene glycol 400
22.3 grams polyethylene glycol 6000
This formulation makes 28 suppositories containing 25 mg progesterone per suppository.

Other Administration Route(s)

Intrauterine device (IUD) Administration
NOTE: This drug is discontinued in the US.
The system can be inserted into the uterus at any time during the menstrual cycle by a trained health-care professional. The preferred time for insertion is at the end of a menstrual cycle or within 2 days to reduce the risk of inserting when there is an undiagnosed pregnancy.
 
Intrauterine device (Progestasert):
Replace every 12 months.
The retrieval threads should be visible.

Adverse Reactions
Severe

spontaneous fetal abortion / Delayed / Incidence not known
suicidal ideation / Delayed / Incidence not known
seizures / Delayed / Incidence not known
anaphylactoid reactions / Rapid / Incidence not known
bronchospasm / Rapid / Incidence not known
angioedema / Rapid / Incidence not known
pancreatitis / Delayed / Incidence not known
hepatic necrosis / Delayed / Incidence not known
hepatic failure / Delayed / Incidence not known
thromboembolism / Delayed / Incidence not known
myocardial infarction / Delayed / Incidence not known
pulmonary embolism / Delayed / Incidence not known
thrombosis / Delayed / Incidence not known
retinal thrombosis / Delayed / Incidence not known
stroke / Early / Incidence not known
dementia / Delayed / Incidence not known
breast cancer / Delayed / Incidence not known
new primary malignancy / Delayed / Incidence not known
ovarian cancer / Delayed / Incidence not known
endometrial cancer / Delayed / Incidence not known

Moderate

cervicitis / Delayed / Incidence not known
dyspareunia / Delayed / Incidence not known
galactorrhea / Delayed / Incidence not known
vaginitis / Delayed / Incidence not known
ovarian cyst / Delayed / Incidence not known
fluid retention / Delayed / Incidence not known
hypotension / Rapid / Incidence not known
sinus tachycardia / Rapid / Incidence not known
hypertension / Early / Incidence not known
edema / Delayed / Incidence not known
dysarthria / Delayed / Incidence not known
depression / Delayed / Incidence not known
migraine / Early / Incidence not known
hot flashes / Early / Incidence not known
wheezing / Rapid / Incidence not known
glossitis / Early / Incidence not known
hepatitis / Delayed / Incidence not known
constipation / Delayed / Incidence not known
dysphagia / Delayed / Incidence not known
cholestasis / Delayed / Incidence not known
gastritis / Delayed / Incidence not known
jaundice / Delayed / Incidence not known
elevated hepatic enzymes / Delayed / Incidence not known
phlebitis / Rapid / Incidence not known
impaired cognition / Early / Incidence not known
vaginal bleeding / Delayed / Incidence not known
endometrial hyperplasia / Delayed / Incidence not known

Mild

pelvic pain / Delayed / 25.0-28.0
headache / Early / 2.0-17.0
irritability / Delayed / 8.0-8.0
infection / Delayed / 1.0-8.0
dizziness / Early / 5.0-5.0
fatigue / Early / 2.0-3.0
amenorrhea / Delayed / Incidence not known
breakthrough bleeding / Delayed / Incidence not known
breast enlargement / Delayed / Incidence not known
dysmenorrhea / Delayed / Incidence not known
hirsutism / Delayed / Incidence not known
leukorrhea / Delayed / Incidence not known
libido decrease / Delayed / Incidence not known
libido increase / Delayed / Incidence not known
mastalgia / Delayed / Incidence not known
melasma / Delayed / Incidence not known
menstrual irregularity / Delayed / Incidence not known
nocturia / Early / Incidence not known
perineal pain / Early / Incidence not known
vaginal discharge / Delayed / Incidence not known
vaginal irritation / Early / Incidence not known
weakness / Early / Incidence not known
weight gain / Delayed / Incidence not known
insomnia / Early / Incidence not known
tremor / Early / Incidence not known
drowsiness / Early / Incidence not known
syncope / Early / Incidence not known
emotional lability / Early / Incidence not known
paresthesias / Delayed / Incidence not known
injection site reaction / Rapid / Incidence not known
fever / Early / Incidence not known
rash / Early / Incidence not known
seborrhea / Delayed / Incidence not known
skin discoloration / Delayed / Incidence not known
acne vulgaris / Delayed / Incidence not known
alopecia / Delayed / Incidence not known
pruritus / Rapid / Incidence not known
urticaria / Rapid / Incidence not known
night sweats / Early / Incidence not known
arthralgia / Delayed / Incidence not known
musculoskeletal pain / Early / Incidence not known
muscle cramps / Delayed / Incidence not known
vomiting / Early / Incidence not known
nausea / Early / Incidence not known
diarrhea / Early / Incidence not known
eructation / Early / Incidence not known
abdominal pain / Early / Incidence not known
appetite stimulation / Delayed / Incidence not known
weight loss / Delayed / Incidence not known
anorexia / Delayed / Incidence not known

Boxed Warning
Breast cancer, cervical cancer, endometrial cancer, endometrial hyperplasia, new primary malignancy, ovarian cancer, uterine cancer, vaginal cancer

Progesterone is contraindicated in patients with pre-existing breast cancer or cancer of reproductive organs, such as cervical cancer, endometrial cancer, ovarian cancer, uterine cancer, or vaginal cancer. Likewise, progesterone formulations should not be used in patients with undiagnosed vaginal bleeding. Progesterone, like other hormones, can influence hormonally-dependent cancers. HORMONE REPLACEMENT THERAPY (HRT): Oral progesterone labeling contains a boxed warning regarding the potential risk for breast cancer (new primary malignancy) in post-menopausal women receiving estrogen and progestin hormonal replacement therapy (HRT). The use of estrogen plus progestin has been reported to result in an increase in abnormal mammograms requiring further evaluation. All women should receive yearly breast examinations by a healthcare provider and perform monthly breast self-examinations. In addition, mammography examinations should be scheduled based on patient age, risk factors, and prior mammogram results. Progestins with estrogens should be prescribed at the lowest effective doses and for the shortest duration consistent with treatment goals and risks for the individual woman. The most important randomized clinical trial providing information about breast cancer in patients taking combined estrogen-progestin HRT regimens is the WHI substudy of estrogen plus progestin. After a mean follow-up of 5.6 years, the WHI estrogen plus progestin substudy reported an increased risk of invasive breast cancer in women who took daily CE plus MPA vs. placebo. In this substudy, prior use of estrogen-alone or estrogen plus progestin therapy was reported by 26% of the women. The relative risk of invasive breast cancer was 1.24, and the absolute risk was 41 versus 33 cases per 10,000 women-years, for estrogen plus progestin compared with placebo. Among women who reported prior use of hormone therapy, the relative risk of invasive breast cancer was 1.86, and the absolute risk was 46 vs. 25 cases per 10,000 women-years for estrogen plus progestin compared with placebo. Among women who reported no prior use of hormone therapy, the relative risk of invasive breast cancer was 1.09, and the absolute risk was 40 vs. 36 cases per 10,000 women-years for estrogen plus progestin compared with placebo. In the same WHI substudy, invasive breast cancers were larger, were more likely to be node positive, and were diagnosed at a more advanced stage in the combined HRT group compared with the placebo group. Metastatic disease was rare, with no apparent difference between the 2 groups. Other prognostic factors, such as histologic subtype, grade and hormone receptor status did not differ between the 2 groups. Consistent with the WHI clinical trial, observational studies have also reported an increased risk of breast cancer for estrogen plus progestin therapy, and a smaller increased risk for estrogen-alone therapy, after several years of use. The risk increased with duration of use, and appeared to return to baseline over about 5 years after stopping treatment (only the observational studies have substantial data on risk after stopping). Observational studies also suggest that the risk of breast cancer was greater, and became apparent earlier, with combined HRT as compared to estrogen-alone therapy. However, these studies have not found significant variation in the risk of breast cancer among different estrogen plus progestin combinations, doses, or routes of administration. Adding a progestin such as progesterone to estrogen HRT has been shown to reduce, but not completely eliminate, the risk of endometrial hyperplasia, which may be a precursor to endometrial cancer. Clinical surveillance of all women using estrogen plus progestin HRT is important. Adequate diagnostic measures, including endometrial sampling when indicated, should be undertaken to rule out malignancy in all cases of undiagnosed persistent or recurring abnormal vaginal bleeding. The WHI estrogen plus progestin substudy reported a statistically non-significant increased risk of ovarian cancer. After an average follow-up of 5.6 years, the relative risk for ovarian cancer for CE plus MPA versus placebo was 1.58 (95% CI, 0.77 to 3.24). The absolute risk for CE plus MPA was 4 versus 3 cases per 10,000 women-years. In some epidemiologic studies, the use of estrogen plus progestin and estrogen-only products, in particular for 5 or more years, has been associated with increased risk of ovarian cancer. However, the duration of exposure associated with increased risk is not consistent across all epidemiologic studies and some report no association.

Cerebrovascular disease, coronary artery disease, hypercholesterolemia, hypertension, myocardial infarction, obesity, stroke, thromboembolic disease, thromboembolism, thrombophlebitis, tobacco smoking, visual disturbance

Progesterone is contraindicated in patients with a history of thrombophlebitis, active or previous history of thromboembolism or thromboembolic disease (including stroke and myocardial infarction). Patients with risk factors for heart disease, thromboembolism, and stroke (e.g., known cerebrovascular disease, hypertension, diabetes mellitus, tobacco smoking, hypercholesterolemia, obesity, etc.) should be monitored closely and managed appropriately. During use of progesterone in patients without a history of thrombosis, the provider should be alert to the earliest manifestations of thrombotic disorder (thrombophlebitis, heart attack, cerebrovascular disorder such as stroke or focal headache with symptoms consistent with cerebral ischemia, pulmonary embolism, or unexplained visual disturbance with ocular pain, which might indicate retinal thrombosis). Should any of these occur or be suspected, progesterone therapy should be discontinued immediately. HORMONAL REPLACEMENT THERAPY (HRT): Progesterone, when used with estrogen therapy for postmenopausal hormone replacement, is associated with cardiovascular and thromboembolic risks, which are highlighted in the oral progesterone boxed warnings. The Women's Health Initiative (WHI) estrogen plus progestin substudy reported an increased risk of deep vein thrombosis (DVT), pulmonary embolism (PE), stroke and myocardial infarction (MI) in postmenopausal women (50 to 79 years of age) during 5.6 years of treatment with estrogen-progestin therapy, relative to placebo. In the WHI estrogen plus progestin substudy, a statistically significant 2-fold greater rate of VTE was reported in women receiving estrogen plus progestin HRT vs. women receiving placebo (35 vs. 17 per 10,000 women-years). Statistically significant increases in risk for both DVT (26 vs. 13 per 10,000 women-years) and PE (18 vs. 8 per 10,000 women-years) were also demonstrated. The increase in VTE risk was demonstrated during the first year and persisted. Estrogens with or without a progestin such as progesterone should not be used for the prevention of cardiac disease or cardiovascular disease (e.g., coronary artery disease) in postmenopausal women. In the WHI estrogen plus progestin substudy, there was a statistically non-significant increased risk of CHD events reported in women receiving daily estrogen plus progestin compared to women receiving placebo (41 vs. 34 per 10,000 women-years). An increase in relative risk was demonstrated in year 1, and a trend toward decreasing relative risk was reported in years 2 through 5. Studies have also shown no cardiovascular benefit to the use of estrogen-progestin therapy for secondary prevention in women with documented cardiac disease or CHD. In the WHI estrogen plus progestin substudy, a statistically significant increased risk of stroke was reported in women 50 to 79 years of age receiving estrogen plus progestin HRT compared to women in the same age group receiving placebo (33 vs. 25 per 10,000 women-years). The increase in risk was demonstrated after the first year and persisted. Women over the age of 65 years were at increased risk for non-fatal stroke.

Asthma, cardiac disease, renal disease

Progesterone should be prescribed cautiously in patients with asthma, congestive heart failure, nephrotic syndrome or other renal disease, or cardiac disease. Hormonal contraceptives can cause fluid retention and may exacerbate any of the above conditions.

Dementia, geriatric

Estrogen/progestin combination therapy has been found to fail to prevent mild cognitive impairment (memory loss) and to increase the risk of dementia in women 65 years and older. The WHIMS study, an ancillary study of the WHI trial to assess the effects of estrogen/progestin therapy on cognitive function in geriatric women (65 years of age or older), found that patients receiving either active treatment or placebo had similar rates of developing mild cognitive impairment. Patients receiving estrogen/progestin combination therapy were more likely than patients receiving placebo to be diagnosed with dementia. The applicability of this finding to women who use estrogen alone or to the typical user of HRT (i.e., younger, symptomatic women taking hormone replacement therapy to relieve menopausal symptoms) is unclear. Administration of estrogen/progestin combination therapy should be avoided in women 65 years of age and older and estrogen/progestin combination therapy should not be used to prevent or treat dementia or preserve cognition (memory).

Common Brand Names

Crinone, Endometrin, PROMETRIUM

Dea Class

Rx

Description

Naturally occurring progestin administered orally,vaginally, and parenterally
Used to treat amenorrhea and abnormal uterine bleeding in women, and to prevent endometrial hyperplasia in postmenopausal women taking estrogen therapy, and off-label for premenstrual dysphoric disorder (PMDD)
Also used to prevent early pregnancy failure in women with corpus luteum insufficiency and to reduce the risk for preterm birth in women with single gestation pregnancy and a history of spontaneous preterm delivery

Dosage And Indications
For the treatment of amenorrhea. Intravaginal dosage (micronized gel) Adult females

Administer the 4% or 8% gel PV every other day up to a total of 6 doses. Use the 8% gel for women who fail to respond to the 4% gel. Note that dosage increases from the 4% gel can only be accomplished by using the 8% gel. Increasing the volume of gel administered does not increase the amount of progesterone absorbed.

Intramuscular dosage Adult females

5 to 10 mg IM once daily for 6 to 8 days, usually started 8 to 10 days prior to the anticipated first day of menstruation. If the endometrium has been proliferative, withdrawal bleeding will generally occur within 48 to 72 hours following cessation of progesterone therapy. Cycles may return to normal after a single course of therapy.

Oral dosage (micronized capsules, e.g., Prometrium) Adult females

For the treatment of secondary amenorrhea, 400 mg PO as a single dose in the evening for 10 days.

For the prevention of endometrial hyperplasia associated with conjugated estrogen replacement therapy in postmenopausal women who have an intact uterus. Oral dosage (micronized capsules, e.g., Prometrium) Adult females with an intact uterus

200 mg PO given as a single dose in the evening for 12 sequential days of every 28-day cycle of daily estrogen therapy.

For the treatment of dysfunctional uterine bleeding secondary to hormonal imbalance. Intramuscular dosage Adult females

5 to 10 mg IM once daily for 6 days. If estrogen therapy is administered concomitantly, progesterone is usually administered after 2 weeks of estrogen therapy. Alternatively, a single dose of 50 to 100 mg IM may be given.

For the treatment of infertility to support embryo implantation and early pregnancy by treating corpus luteum insufficiency, usually as part of an Assisted Reproductive Technology (ART) program. Vaginal dosage (Endometrin vaginal insert) Adult females

100 mg PV 2 to 3 times per day starting the day after oocyte retrieval and continuing for up to 10 weeks total duration. In women 35 years and older, the appropriate dosage for efficacy has not been definitively determined.

Vaginal dosage (micronized progesterone vaginal gels; e.g., Crinone) Adult females

90 mg (8% gel) PV once daily. In women with partial or complete ovarian failure, 90 mg PV twice daily is recommended. If pregnancy occurs, treatment may be continued until placental autonomy is achieved, up to 10 to 12 weeks of gestation.

Intramuscular dosage† Adult females

12.5 mg IM once daily beginning at the onset of ovulation, may be continued for up to the 11th week of gestation. Alternatively for ART programs, 25 to 100 mg IM once daily starting at oocyte retrieval and continuing during the luteal phase or until 10 to 12 weeks gestation.

For the treatment of symptoms associated with premenstrual syndrome (PMS)†. Oral dosage (micronized capsules, e.g., Prometrium) Adults

300 mg PO 4 times per day has been used, with adjustment to patient response; efficacy has not been proven. One meta-analysis found that few studies of oral or vaginal progesterone for this indication were of sufficient quality; the trials meeting criteria for analysis did not establish whether progesterone treatment was effective for PMS or not.

For preterm delivery prophylaxis†. Vaginal dosage (extemporaneously compounded suppositories) Adult females

The usual dosage is 100 mg or 200 mg vaginally as a suppository once daily at bedtime starting at at 16 to 24 weeks gestation and continuing through 34 weeks gestation. Progesterone helps reduce the risk for preterm birth in selected patients. In women with single gestation pregnancy and a history of spontaneous preterm delivery, antenatal progesterone therapy effectively decreases the risk of a recurrent preterm delivery. It is not yet clear if the drug is routinely beneficial at reducing risk for preterm birth in multiple gestation pregnancies.

Vaginal dosage (progesterone 8% vaginal gel) Adult females

1 applicator (each applicator delivers 1.125 grams gel containing 90 mg progesterone) vaginally once daily at bedtime starting at at 16 to 24 weeks gestation and continuing through 34 weeks gestation. Progesterone helps reduce the risk for preterm birth in selected patients. In women with single gestation pregnancy and a history of spontaneous preterm delivery, antenatal progesterone therapy effectively decreases the risk of a recurrent preterm delivery. In one study, vaginal progesterone gel was also associated with a significant reduction in the rate of preterm birth before 28 weeks and 35 weeks, and a significant reduction in the incidence of neonatal respiratory distress syndrome, any neonatal morbidity or mortality event, and birth weight less than 1500 grams. It is not yet clear if the drug is routinely beneficial at reducing risk for preterm birth in multiple gestation pregnancies.

†Indicates off-label use

Dosing Considerations
Hepatic Impairment

Progesterone is considered contraindicated for use in patients with significant hepatic disease.

Renal Impairment

Specific guidelines for dosage adjustments in renal impairment are not available; it appears that no dosage adjustments are needed.

Drug Interactions

Adagrasib: (Moderate) Use caution if coadministration of adagrasib with progestins is necessary, as the systemic exposure of progestins may be increased resulting in an increase in treatment-related adverse reactions. Progestins are metabolized primarily by hydroxylation via a CYP3A; adagrasib is a strong CYP3A inhibitor.
Alogliptin: (Minor) Estrogens, progestins, or oral contraceptives can decrease the hypoglycemic effects of antidiabetic agents by impairing glucose tolerance. Changes in glucose tolerance occur more commonly in patients receiving > 50 mcg of ethinyl estradiol per day. The presence or absence of a concomitant progestin may influence the significance of this effect. Patients receiving antidiabetic agents should be closely monitored for changes in diabetic control when hormone therapy is instituted or discontinued.
Alogliptin; Metformin: (Minor) Estrogens, progestins, or oral contraceptives can decrease the hypoglycemic effects of antidiabetic agents by impairing glucose tolerance. Changes in glucose tolerance occur more commonly in patients receiving > 50 mcg of ethinyl estradiol per day. The presence or absence of a concomitant progestin may influence the significance of this effect. Patients receiving antidiabetic agents should be closely monitored for changes in diabetic control when hormone therapy is instituted or discontinued. (Minor) Patients receiving antidiabetic agents like metformin should be closely monitored for signs indicating changes in diabetic control when therapy with progestins is instituted or discontinued. Progestins can impair glucose tolerance.
Alogliptin; Pioglitazone: (Minor) Estrogens, progestins, or oral contraceptives can decrease the hypoglycemic effects of antidiabetic agents by impairing glucose tolerance. Changes in glucose tolerance occur more commonly in patients receiving > 50 mcg of ethinyl estradiol per day. The presence or absence of a concomitant progestin may influence the significance of this effect. Patients receiving antidiabetic agents should be closely monitored for changes in diabetic control when hormone therapy is instituted or discontinued. (Minor) Progestins can impair glucose tolerance. Patients receiving antidiabetic agents should be closely monitored for signs indicating changes in diabetic control when therapy with progestins is instituted or discontinued.
Alpha-glucosidase Inhibitors: (Minor) Progestins can impair glucose tolerance. Patients receiving antidiabetic agents should be closely monitored for signs indicating changes in diabetic control when therapy with progestins is instituted or discontinued.
Amobarbital: (Moderate) Barbiturates can accelerate the hepatic clearance of progestins. For hormonal contraceptives, this interaction could result in unintended pregnancy or breakthrough bleeding. For patients regularly taking a barbiturate, an alternative or back-up method of contraception may be advisable to ensure contraceptive reliability during the use of the barbiturate, and for 1 month following the discontinuation of barbiturate use. The exception is the use of levonorgestrel progestin IUDs, which have not been reported to interact and appear to maintain reliable efficacy. Pregnancy has been reported during therapy with both estrogen- and/or progestin-based oral contraceptives in patients receiving barbiturates (e.g., phenobarbital). For patients taking progestins for other indications, like hormone replacement, monitor the patient for signs and symptoms of reduced therapeutic efficacy or need for dosage adjustment.
Amoxicillin; Clarithromycin; Omeprazole: (Moderate) Use caution if coadministration of clarithromycin with progesterone is necessary, as the systemic exposure of progesterone may be increased resulting in an increase in treatment-related adverse reactions. Clarithromycin is a strong CYP3A4 inhibitor. Progesterone is metabolized primarily by hydroxylation via a CYP3A4. This interaction does not apply to vaginal preparations of progesterone (e.g., Crinone, Endometrin).
Apalutamide: (Major) Progestins are susceptible to drug interactions with hepatic enzyme inducing drugs such as apalutamide. Concurrent administration of apalutamide with progestins, oral contraceptives, or non-oral combination contraceptives may reduce hormonal concentrations. Progestins are CYP3A4 substrates and apalutamide is a strong CYP3A4 inducer. If the hormone is used for contraception, an alternate or additional form of contraception should be considered. Higher-dose hormonal regimens may be indicated where acceptable or applicable. The alternative or additional contraceptive agent may need to be continued for 1 month after discontinuation of apalutamide. Monitor hormonal replacement therapy for loss of efficacy while on apalutamide, with dose adjustments as needed. Women taking hormonal replacement and apalutamide should report breakthrough bleeding to their prescribers. This interaction does not apply to vaginal preparations of progesterone (e.g., Crinone, Endometrin).
Aprepitant, Fosaprepitant: (Major) If aprepitant, fosaprepitant is coadministered with hormonal contraceptives, including hormonal contraceptive devices (skin patches, implants, and hormonal IUDs), use an alternative or back-up non-hormonal method of contraception (e.g., condoms, spermicides) during treatment and for at least 1 month following the last dose of aprepitant, fosaprepitant. The efficacy of progestins may be reduced when coadministered with aprepitant, fosaprepitant and for 28 days after the last dose. The exact mechanism for this interaction has not been described. Progestins are CYP3A4 substrates and aprepitant, fosaprepitant is a CYP3A4 inducer; however, aprepitant, fosaprepitant is also a dose-dependent weak-to-moderate CYP3A4 inhibitor. When administered as an oral 3-day regimen (125mg/80mg/80mg) in combination with ondansetron and dexamethasone, aprepitant decreased trough concentrations of ethinyl estradiol and norethindrone by up to 64% for 3 weeks post-treatment. When ethinyl estradiol and norgestimate were administered on days 1 to 21 and aprepitant (40mg) give as a single dose on day 8, the AUC of ethinyl estradiol decreased by 4% on day 8 and by 29% on day 12; the AUC of norelgestromin increased by 18% on day 8, and decreased by 10% on day 12. Trough concentrations of both ethinyl estradiol and norelgestromin were generally lower after coadministration of aprepitant (40mg) on day 8 compared to administration without aprepitant. Specific studies have not been done with other hormonal contraceptives (e.g., progestins, non-oral combination contraceptives), an alternative or additional non-hormonal method of birth control during treatment and for 28 days after treatment is prudent to avoid potential for contraceptive failure. The clinical significance of this is not known since aprepitant, fosaprepitant is only used intermittently.
Armodafinil: (Major) Armodafinil may cause failure of oral contraceptives or hormonal contraceptive-containing implants or devices due to induction of CYP3A4 isoenzyme metabolism of estrogens and/or the progestins in these products. Female patients of child-bearing potential should be advised to discuss contraceptive options with their health care provider to prevent unintended pregnancies. An alternative method or an additional method of contraception should be utilized during armodafinil therapy and continued for one month after armodafinil discontinuation.
Artemether; Lumefantrine: (Major) Although no formal drug interaction studies have been performed, the manufacturer states that artemether; lumefantrine may reduce the effectiveness of hormonal contraceptives, including progestin contraceptives (i.e., progesterone). This may be due to a CYP3A4 interaction. Artemether; lumefantrine is a substrate and ethinyl estradiol is a substrate/inhibitor of the CYP3A4 isoenzyme. Additional use of a non-hormonal method of birth control is recommended.
Aspirin, ASA; Butalbital; Caffeine: (Moderate) Barbiturates can accelerate the hepatic clearance of progestins. For hormonal contraceptives, this interaction could result in unintended pregnancy or breakthrough bleeding. For patients regularly taking a barbiturate, an alternative or back-up method of contraception may be advisable to ensure contraceptive reliability during the use of the barbiturate, and for 1 month following the discontinuation of barbiturate use. The exception is the use of levonorgestrel progestin IUDs, which have not been reported to interact and appear to maintain reliable efficacy. Pregnancy has been reported during therapy with both estrogen- and/or progestin-based oral contraceptives in patients receiving barbiturates (e.g., phenobarbital). For patients taking progestins for other indications, like hormone replacement, monitor the patient for signs and symptoms of reduced therapeutic efficacy or need for dosage adjustment.
Atazanavir: (Moderate) Use caution if coadministration of atazanavir with progesterone is necessary, as the systemic exposure of progesterone may be increased resulting in an increase in treatment-related adverse reactions. Atazanavir is a strong CYP3A4 inhibitor. Progesterone is metabolized primarily by hydroxylation via a CYP3A4. This interaction does not apply to vaginal preparations of progesterone (e.g., Crinone, Endometrin).
Atazanavir; Cobicistat: (Major) Consider the benefits and risk of administering antiretroviral regimens containing cobicistat with progesterone. Insufficient data are available to make dosage recommendations, particularly when cobicistat is combined in other antiviral regimens. It is not clear how cobicistat alters various progestin-only agents used for contraception, fertility or luteal support, or for hormone replacement therapy (HRT). Instruct women to report any breakthrough bleeding or other adverse effects (e.g., insulin resistance, dyslipidemia, and acne) to their prescribers. There is a potential for altered efficacy for combined hormonal contraceptives. Consider alternative methods of contraception, such as condoms, to prevent unwanted pregnancy and transmission of HIV/AIDS. When progestins are used for other purposes, monitor for altered clinical response to hormonal therapy. The metabolism of progesterone may also be inhibited by cobicistat, a strong inhibitor of the CYP3A4 hepatic enzyme. This interaction does not apply to vaginal preparations of progesterone (e.g., Crinone, Endometrin). (Moderate) Use caution if coadministration of atazanavir with progesterone is necessary, as the systemic exposure of progesterone may be increased resulting in an increase in treatment-related adverse reactions. Atazanavir is a strong CYP3A4 inhibitor. Progesterone is metabolized primarily by hydroxylation via a CYP3A4. This interaction does not apply to vaginal preparations of progesterone (e.g., Crinone, Endometrin).
Barbiturates: (Moderate) Barbiturates can accelerate the hepatic clearance of progestins. For hormonal contraceptives, this interaction could result in unintended pregnancy or breakthrough bleeding. For patients regularly taking a barbiturate, an alternative or back-up method of contraception may be advisable to ensure contraceptive reliability during the use of the barbiturate, and for 1 month following the discontinuation of barbiturate use. The exception is the use of levonorgestrel progestin IUDs, which have not been reported to interact and appear to maintain reliable efficacy. Pregnancy has been reported during therapy with both estrogen- and/or progestin-based oral contraceptives in patients receiving barbiturates (e.g., phenobarbital). For patients taking progestins for other indications, like hormone replacement, monitor the patient for signs and symptoms of reduced therapeutic efficacy or need for dosage adjustment.
Belzutifan: (Major) Women taking both progestins and belzutifan should report breakthrough bleeding to their prescribers. An alternate or additional form of contraception should be considered in patients prescribed belzutifan. Higher-dose hormonal regimens may be indicated where acceptable or applicable. The alternative or additional contraceptive agent may need to be continued for 1 month after discontinuation of belzutifan. For patients on hormone replacement treatments (HRT) with progestins, monitor for altered clinical response, such as increased hot flashes, vaginal dryness, changes in withdrawal bleeding, or other signs of decreased hormonal efficacy. Progestins are CYP3A4 substrates and belzutifan is a weak CYP3A4 inducer.
Bexarotene: (Major) Bexarotene capsules may theoretically increase the rate of metabolism and reduce plasma concentrations of substrates metabolized by CYP3A4, including oral contraceptives. It is recommended that two reliable forms of contraception be used simultaneously during oral bexarotene therapy. It is strongly recommended that one of the forms of contraception be non-hormonal. Additionally, because of possible CYP3A4 induction, bexarotene may also decrease the efficacy of hormones used for hormone replacement therapy.
Bosentan: (Major) Hormonal contraceptives should not be used as the sole method to prevent pregnancy in patients receiving bosentan. There is a possibility of contraceptive failure when bosentan is coadministered with products containing estrogens and/or progestins. Bosentan is teratogenic. To prevent pregnancy, females of reproductive potential must use 2 acceptable contraception methods during treatment and for 1 month after discontinuation of bosentan therapy. The patient may choose 1 highly effective contraceptive form, including an intrauterine device (IUD) or tubal sterilization, a combination of a hormonal contraceptive with a barrier method, or 2 barrier methods. If a male partner's vasectomy is chosen as a method of contraception, a hormonal or barrier method must still be used by the female patient. Hormonal contraceptives, including oral contraceptives or non-oral combination contraceptives (injectable, transdermal, and implantable contraceptives) may not be reliably effective in the presence of bosentan, since many contraceptive drugs are metabolized by CYP3A4 isoenzymes and bosentan is a significant inducer of CYP3A enzymes. Decreases in hormonal exposure have been documented in drug interaction studies of bosentan with hormonal contraception. Additionally, estrogens and progestins used for hormone replacement therapy (HRT) may also be less effective; patients should be monitored for changes in efficacy such as breakthrough bleeding or an increase in hot flashes. Dosage adjustments may be necessary.
Bromocriptine: (Minor) Bromocriptine is used to restore ovulation and ovarian function in amenorrheic women. Progestins can cause amenorrhea and, therefore, counteract the desired effects of bromocriptine. Concurrent use is not recommended; an alternate form of contraception is recommended during bromocriptine therapy.
Butabarbital: (Moderate) Barbiturates can accelerate the hepatic clearance of progestins. For hormonal contraceptives, this interaction could result in unintended pregnancy or breakthrough bleeding. For patients regularly taking a barbiturate, an alternative or back-up method of contraception may be advisable to ensure contraceptive reliability during the use of the barbiturate, and for 1 month following the discontinuation of barbiturate use. The exception is the use of levonorgestrel progestin IUDs, which have not been reported to interact and appear to maintain reliable efficacy. Pregnancy has been reported during therapy with both estrogen- and/or progestin-based oral contraceptives in patients receiving barbiturates (e.g., phenobarbital). For patients taking progestins for other indications, like hormone replacement, monitor the patient for signs and symptoms of reduced therapeutic efficacy or need for dosage adjustment.
Butalbital; Acetaminophen: (Moderate) Barbiturates can accelerate the hepatic clearance of progestins. For hormonal contraceptives, this interaction could result in unintended pregnancy or breakthrough bleeding. For patients regularly taking a barbiturate, an alternative or back-up method of contraception may be advisable to ensure contraceptive reliability during the use of the barbiturate, and for 1 month following the discontinuation of barbiturate use. The exception is the use of levonorgestrel progestin IUDs, which have not been reported to interact and appear to maintain reliable efficacy. Pregnancy has been reported during therapy with both estrogen- and/or progestin-based oral contraceptives in patients receiving barbiturates (e.g., phenobarbital). For patients taking progestins for other indications, like hormone replacement, monitor the patient for signs and symptoms of reduced therapeutic efficacy or need for dosage adjustment.
Butalbital; Acetaminophen; Caffeine: (Moderate) Barbiturates can accelerate the hepatic clearance of progestins. For hormonal contraceptives, this interaction could result in unintended pregnancy or breakthrough bleeding. For patients regularly taking a barbiturate, an alternative or back-up method of contraception may be advisable to ensure contraceptive reliability during the use of the barbiturate, and for 1 month following the discontinuation of barbiturate use. The exception is the use of levonorgestrel progestin IUDs, which have not been reported to interact and appear to maintain reliable efficacy. Pregnancy has been reported during therapy with both estrogen- and/or progestin-based oral contraceptives in patients receiving barbiturates (e.g., phenobarbital). For patients taking progestins for other indications, like hormone replacement, monitor the patient for signs and symptoms of reduced therapeutic efficacy or need for dosage adjustment.
Butalbital; Acetaminophen; Caffeine; Codeine: (Moderate) Barbiturates can accelerate the hepatic clearance of progestins. For hormonal contraceptives, this interaction could result in unintended pregnancy or breakthrough bleeding. For patients regularly taking a barbiturate, an alternative or back-up method of contraception may be advisable to ensure contraceptive reliability during the use of the barbiturate, and for 1 month following the discontinuation of barbiturate use. The exception is the use of levonorgestrel progestin IUDs, which have not been reported to interact and appear to maintain reliable efficacy. Pregnancy has been reported during therapy with both estrogen- and/or progestin-based oral contraceptives in patients receiving barbiturates (e.g., phenobarbital). For patients taking progestins for other indications, like hormone replacement, monitor the patient for signs and symptoms of reduced therapeutic efficacy or need for dosage adjustment.
Butalbital; Aspirin; Caffeine; Codeine: (Moderate) Barbiturates can accelerate the hepatic clearance of progestins. For hormonal contraceptives, this interaction could result in unintended pregnancy or breakthrough bleeding. For patients regularly taking a barbiturate, an alternative or back-up method of contraception may be advisable to ensure contraceptive reliability during the use of the barbiturate, and for 1 month following the discontinuation of barbiturate use. The exception is the use of levonorgestrel progestin IUDs, which have not been reported to interact and appear to maintain reliable efficacy. Pregnancy has been reported during therapy with both estrogen- and/or progestin-based oral contraceptives in patients receiving barbiturates (e.g., phenobarbital). For patients taking progestins for other indications, like hormone replacement, monitor the patient for signs and symptoms of reduced therapeutic efficacy or need for dosage adjustment.
Canagliflozin: (Minor) Progestins can impair glucose tolerance. Patients receiving antidiabetic agents should be closely monitored for signs indicating changes in diabetic control when therapy with progestins is instituted or discontinued.
Canagliflozin; Metformin: (Minor) Patients receiving antidiabetic agents like metformin should be closely monitored for signs indicating changes in diabetic control when therapy with progestins is instituted or discontinued. Progestins can impair glucose tolerance. (Minor) Progestins can impair glucose tolerance. Patients receiving antidiabetic agents should be closely monitored for signs indicating changes in diabetic control when therapy with progestins is instituted or discontinued.
Carbamazepine: (Major) Advise patients taking progestin hormones for contraception to consider an alternate or additional form of contraception, such as nonhormonal and/or barrier methods, during and for at least 1 month following discontinuation of carbamazepine. Higher-dose hormonal regimens may also be considered. Patients taking these hormones for other indications may need to be monitored for reduced clinical effect while on carbamazepine, with dose adjustments made based on clinical efficacy. Progestins are CYP3A substrates and carbamazepine is a strong CYP3A inducer. Concurrent administration may increase progestin elimination. This interaction does not apply to vaginal preparations of progesterone (e.g., Crinone, Endometrin).
Cenobamate: (Major) Women taking both progestins and cenobamate should report breakthrough bleeding to their prescribers. If used for contraception, an alternate or additional form of contraception should be considered in patients prescribed cenobamate. Higher-dose hormonal regimens may be indicated where acceptable or applicable. The alternative or additional contraceptive agent may need to be continued for 1 month after discontinuation of cenobamate. Patients taking these hormones for other indications may need to be monitored for reduced clinical effect while on cenobamate, with dose adjustments made based on clinical efficacy. Progestins are CYP3A4 substrates and cenobamate is a moderate CYP3A4 inducer. Concurrent administration may increase progestin elimination.
Ceritinib: (Moderate) Use caution if coadministration of ceritinib with progesterone is necessary, as the systemic exposure of progesterone may be increased resulting in an increase in treatment-related adverse reactions. Ceritinib is a strong CYP3A4 inhibitor. Progesterone is metabolized primarily by hydroxylation via a CYP3A4. This interaction does not apply to vaginal preparations of progesterone (e.g., Crinone, Endometrin).
Chloramphenicol: (Moderate) Use caution if coadministration of chloramphenicol with progesterone is necessary, as the systemic exposure of progesterone may be increased resulting in an increase in treatment-related adverse reactions. Chloramphenicol is a strong CYP3A4 inhibitor. Progesterone is metabolized primarily by hydroxylation via a CYP3A4. This interaction does not apply to vaginal preparations of progesterone (e.g., Crinone, Endometrin).
Chlorpropamide: (Minor) Progestins can impair glucose tolerance. Patients receiving antidiabetic agents should be closely monitored for signs indicating changes in diabetic control when therapy with progestins is instituted or discontinued.
Cimetidine: (Minor) The metabolism of progesterone may be inhibited by cimetidine, an inhibitor of cytochrome P450 3A4 hepatic enzymes.
Clarithromycin: (Moderate) Use caution if coadministration of clarithromycin with progesterone is necessary, as the systemic exposure of progesterone may be increased resulting in an increase in treatment-related adverse reactions. Clarithromycin is a strong CYP3A4 inhibitor. Progesterone is metabolized primarily by hydroxylation via a CYP3A4. This interaction does not apply to vaginal preparations of progesterone (e.g., Crinone, Endometrin).
Clobazam: (Major) The addition of non-hormonal forms of contraception are recommended during concurrent use of clobazam and hormonal contraceptives. Concurrent administration of clobazam, a weak CYP3A4 inducer, with progestins may increase the elimination of these hormones. The additional contraceptive agent may need to be continued for 1 month after discontinuation of the interacting medication. Patients taking these hormones for indications other than contraception may need to be monitored for reduced clinical effect while on clobazam, with dose adjustments made based on clinical efficacy.
Clotrimazole: (Moderate) Vaginal preparations of progesterone (e.g., Crinone, Endometrin, and Prochieve) should not be used with other intravaginal products (e.g., vaginal antifungals, such as clotrimazole, miconazole nitrate, terconazole, or tioconazole vaginal) as concurrent use may alter progesterone release and absorption from the vagina. Separate the times of administration to avoid the interaction. The manufacturers of Crinone and Prochieve indicate that other intravaginal products can be used as long as 6 hours has lapsed either before or after vaginal administration of progesterone. Endometrin is generally not recommended for use with other vaginal products (e.g., antifungal products) as this may alter progesterone release and absorption from the vaginal insert and the potential for interaction has not been formally assessed; use other vaginal products if medically necessary, but be aware that the response to Endometrin may be altered.
Clotrimazole; Betamethasone: (Moderate) Vaginal preparations of progesterone (e.g., Crinone, Endometrin, and Prochieve) should not be used with other intravaginal products (e.g., vaginal antifungals, such as clotrimazole, miconazole nitrate, terconazole, or tioconazole vaginal) as concurrent use may alter progesterone release and absorption from the vagina. Separate the times of administration to avoid the interaction. The manufacturers of Crinone and Prochieve indicate that other intravaginal products can be used as long as 6 hours has lapsed either before or after vaginal administration of progesterone. Endometrin is generally not recommended for use with other vaginal products (e.g., antifungal products) as this may alter progesterone release and absorption from the vaginal insert and the potential for interaction has not been formally assessed; use other vaginal products if medically necessary, but be aware that the response to Endometrin may be altered.
Cobicistat: (Major) Consider the benefits and risk of administering antiretroviral regimens containing cobicistat with progesterone. Insufficient data are available to make dosage recommendations, particularly when cobicistat is combined in other antiviral regimens. It is not clear how cobicistat alters various progestin-only agents used for contraception, fertility or luteal support, or for hormone replacement therapy (HRT). Instruct women to report any breakthrough bleeding or other adverse effects (e.g., insulin resistance, dyslipidemia, and acne) to their prescribers. There is a potential for altered efficacy for combined hormonal contraceptives. Consider alternative methods of contraception, such as condoms, to prevent unwanted pregnancy and transmission of HIV/AIDS. When progestins are used for other purposes, monitor for altered clinical response to hormonal therapy. The metabolism of progesterone may also be inhibited by cobicistat, a strong inhibitor of the CYP3A4 hepatic enzyme. This interaction does not apply to vaginal preparations of progesterone (e.g., Crinone, Endometrin).
Danazol: (Minor) The metabolism of progesterone may be inhibited by danazol, a known inhibitor of cytochrome P450 3A4 hepatic enzymes.
Dapagliflozin: (Minor) Estrogens, progestins, or oral contraceptives can decrease the hypoglycemic effects of antidiabetic agents by impairing glucose tolerance. Changes in glucose tolerance occur more commonly in patients receiving > 50 mcg of ethinyl estradiol per day. The presence or absence of a concomitant progestin may influence the significance of this effect. Patients receiving antidiabetic agents should be closely monitored for changes in diabetic control when hormone therapy is instituted or discontinued.
Dapagliflozin; Metformin: (Minor) Estrogens, progestins, or oral contraceptives can decrease the hypoglycemic effects of antidiabetic agents by impairing glucose tolerance. Changes in glucose tolerance occur more commonly in patients receiving > 50 mcg of ethinyl estradiol per day. The presence or absence of a concomitant progestin may influence the significance of this effect. Patients receiving antidiabetic agents should be closely monitored for changes in diabetic control when hormone therapy is instituted or discontinued. (Minor) Patients receiving antidiabetic agents like metformin should be closely monitored for signs indicating changes in diabetic control when therapy with progestins is instituted or discontinued. Progestins can impair glucose tolerance.
Dapagliflozin; Saxagliptin: (Minor) Estrogens, progestins, or oral contraceptives can decrease the hypoglycemic effects of antidiabetic agents by impairing glucose tolerance. Changes in glucose tolerance occur more commonly in patients receiving > 50 mcg of ethinyl estradiol per day. The presence or absence of a concomitant progestin may influence the significance of this effect. Patients receiving antidiabetic agents should be closely monitored for changes in diabetic control when hormone therapy is instituted or discontinued. (Minor) Progestins can decrease the hypoglycemic effects of antidiabetic agents by impairing glucose tolerance. Patients receiving antidiabetic agents should be closely monitored for changes in diabetic control when hormone therapy is instituted or discontinued.
Darunavir: (Moderate) Use caution if coadministration of darunavir with progesterone is necessary, as the systemic exposure of progesterone may be increased resulting in an increase in treatment-related adverse reactions. Darunavir is a strong CYP3A4 inhibitor. Progesterone is metabolized primarily by hydroxylation via a CYP3A4. This interaction does not apply to vaginal preparations of progesterone (e.g., Crinone, Endometrin).
Darunavir; Cobicistat: (Major) Consider the benefits and risk of administering antiretroviral regimens containing cobicistat with progesterone. Insufficient data are available to make dosage recommendations, particularly when cobicistat is combined in other antiviral regimens. It is not clear how cobicistat alters various progestin-only agents used for contraception, fertility or luteal support, or for hormone replacement therapy (HRT). Instruct women to report any breakthrough bleeding or other adverse effects (e.g., insulin resistance, dyslipidemia, and acne) to their prescribers. There is a potential for altered efficacy for combined hormonal contraceptives. Consider alternative methods of contraception, such as condoms, to prevent unwanted pregnancy and transmission of HIV/AIDS. When progestins are used for other purposes, monitor for altered clinical response to hormonal therapy. The metabolism of progesterone may also be inhibited by cobicistat, a strong inhibitor of the CYP3A4 hepatic enzyme. This interaction does not apply to vaginal preparations of progesterone (e.g., Crinone, Endometrin). (Moderate) Use caution if coadministration of darunavir with progesterone is necessary, as the systemic exposure of progesterone may be increased resulting in an increase in treatment-related adverse reactions. Darunavir is a strong CYP3A4 inhibitor. Progesterone is metabolized primarily by hydroxylation via a CYP3A4. This interaction does not apply to vaginal preparations of progesterone (e.g., Crinone, Endometrin).
Darunavir; Cobicistat; Emtricitabine; Tenofovir alafenamide: (Major) Consider the benefits and risk of administering antiretroviral regimens containing cobicistat with progesterone. Insufficient data are available to make dosage recommendations, particularly when cobicistat is combined in other antiviral regimens. It is not clear how cobicistat alters various progestin-only agents used for contraception, fertility or luteal support, or for hormone replacement therapy (HRT). Instruct women to report any breakthrough bleeding or other adverse effects (e.g., insulin resistance, dyslipidemia, and acne) to their prescribers. There is a potential for altered efficacy for combined hormonal contraceptives. Consider alternative methods of contraception, such as condoms, to prevent unwanted pregnancy and transmission of HIV/AIDS. When progestins are used for other purposes, monitor for altered clinical response to hormonal therapy. The metabolism of progesterone may also be inhibited by cobicistat, a strong inhibitor of the CYP3A4 hepatic enzyme. This interaction does not apply to vaginal preparations of progesterone (e.g., Crinone, Endometrin). (Moderate) Use caution if coadministration of darunavir with progesterone is necessary, as the systemic exposure of progesterone may be increased resulting in an increase in treatment-related adverse reactions. Darunavir is a strong CYP3A4 inhibitor. Progesterone is metabolized primarily by hydroxylation via a CYP3A4. This interaction does not apply to vaginal preparations of progesterone (e.g., Crinone, Endometrin).
Delavirdine: (Moderate) Use caution if coadministration of delavirdine with progesterone is necessary, as the systemic exposure of progesterone may be increased resulting in an increase in treatment-related adverse reactions. Delavirdine is a strong CYP3A4 inhibitor. Progesterone is metabolized primarily by hydroxylation via a CYP3A4. This interaction does not apply to vaginal preparations of progesterone (e.g., Crinone, Endometrin).
Diltiazem: (Minor) The metabolism of progesterone may be decreased by inhibitors of cytochrome P450 3A4 hepatic enzymes, such as diltiazem.
Doxorubicin Liposomal: (Minor) Enhanced doxorubicin-induced neutropenia and thrombocytopenia may occur if coadministered with progesterone.
Doxorubicin: (Minor) Enhanced doxorubicin-induced neutropenia and thrombocytopenia may occur if coadministered with progesterone.
Elvitegravir; Cobicistat; Emtricitabine; Tenofovir Alafenamide: (Major) Consider the benefits and risk of administering antiretroviral regimens containing cobicistat with progesterone. Insufficient data are available to make dosage recommendations, particularly when cobicistat is combined in other antiviral regimens. It is not clear how cobicistat alters various progestin-only agents used for contraception, fertility or luteal support, or for hormone replacement therapy (HRT). Instruct women to report any breakthrough bleeding or other adverse effects (e.g., insulin resistance, dyslipidemia, and acne) to their prescribers. There is a potential for altered efficacy for combined hormonal contraceptives. Consider alternative methods of contraception, such as condoms, to prevent unwanted pregnancy and transmission of HIV/AIDS. When progestins are used for other purposes, monitor for altered clinical response to hormonal therapy. The metabolism of progesterone may also be inhibited by cobicistat, a strong inhibitor of the CYP3A4 hepatic enzyme. This interaction does not apply to vaginal preparations of progesterone (e.g., Crinone, Endometrin).
Elvitegravir; Cobicistat; Emtricitabine; Tenofovir Disoproxil Fumarate: (Major) Consider the benefits and risk of administering antiretroviral regimens containing cobicistat with progesterone. Insufficient data are available to make dosage recommendations, particularly when cobicistat is combined in other antiviral regimens. It is not clear how cobicistat alters various progestin-only agents used for contraception, fertility or luteal support, or for hormone replacement therapy (HRT). Instruct women to report any breakthrough bleeding or other adverse effects (e.g., insulin resistance, dyslipidemia, and acne) to their prescribers. There is a potential for altered efficacy for combined hormonal contraceptives. Consider alternative methods of contraception, such as condoms, to prevent unwanted pregnancy and transmission of HIV/AIDS. When progestins are used for other purposes, monitor for altered clinical response to hormonal therapy. The metabolism of progesterone may also be inhibited by cobicistat, a strong inhibitor of the CYP3A4 hepatic enzyme. This interaction does not apply to vaginal preparations of progesterone (e.g., Crinone, Endometrin).
Empagliflozin: (Minor) Estrogens, progestins, or oral contraceptives can decrease the hypoglycemic effects of antidiabetic agents by impairing glucose tolerance. Changes in glucose tolerance occur more commonly in patients receiving > 50 mcg of ethinyl estradiol per day. The presence or absence of a concomitant progestin may influence the significance of this effect. Patients receiving antidiabetic agents should be closely monitored for changes in diabetic control when hormone therapy is instituted or discontinued.
Empagliflozin; Linagliptin: (Minor) Estrogens, progestins, or oral contraceptives can decrease the hypoglycemic effects of antidiabetic agents by impairing glucose tolerance. Changes in glucose tolerance occur more commonly in patients receiving > 50 mcg of ethinyl estradiol per day. The presence or absence of a concomitant progestin may influence the significance of this effect. Patients receiving antidiabetic agents should be closely monitored for changes in diabetic control when hormone therapy is instituted or discontinued. (Minor) Estrogens, progestins, or oral contraceptives can decrease the hypoglycemic effects of antidiabetic agents by impairing glucose tolerance. Changes in glucose tolerance occur more commonly in patients receiving > 50 mcg of ethinyl estradiol per day. The presence or absence of a concomitant progestin may influence the significance of this effect. Patients receiving antidiabetic agents, such as linagliptin, should be closely monitored for changes in diabetic control when hormone therapy is instituted or discontinued.
Empagliflozin; Linagliptin; Metformin: (Minor) Estrogens, progestins, or oral contraceptives can decrease the hypoglycemic effects of antidiabetic agents by impairing glucose tolerance. Changes in glucose tolerance occur more commonly in patients receiving > 50 mcg of ethinyl estradiol per day. The presence or absence of a concomitant progestin may influence the significance of this effect. Patients receiving antidiabetic agents should be closely monitored for changes in diabetic control when hormone therapy is instituted or discontinued. (Minor) Estrogens, progestins, or oral contraceptives can decrease the hypoglycemic effects of antidiabetic agents by impairing glucose tolerance. Changes in glucose tolerance occur more commonly in patients receiving > 50 mcg of ethinyl estradiol per day. The presence or absence of a concomitant progestin may influence the significance of this effect. Patients receiving antidiabetic agents, such as linagliptin, should be closely monitored for changes in diabetic control when hormone therapy is instituted or discontinued. (Minor) Patients receiving antidiabetic agents like metformin should be closely monitored for signs indicating changes in diabetic control when therapy with progestins is instituted or discontinued. Progestins can impair glucose tolerance.
Empagliflozin; Metformin: (Minor) Estrogens, progestins, or oral contraceptives can decrease the hypoglycemic effects of antidiabetic agents by impairing glucose tolerance. Changes in glucose tolerance occur more commonly in patients receiving > 50 mcg of ethinyl estradiol per day. The presence or absence of a concomitant progestin may influence the significance of this effect. Patients receiving antidiabetic agents should be closely monitored for changes in diabetic control when hormone therapy is instituted or discontinued. (Minor) Patients receiving antidiabetic agents like metformin should be closely monitored for signs indicating changes in diabetic control when therapy with progestins is instituted or discontinued. Progestins can impair glucose tolerance.
Enzalutamide: (Major) Avoid coadministration of enzalutamide with progestins if used for contraception; consider an alternate or additional form of contraception. The alternative or additional contraceptive agent may need to be continued for 1 month after discontinuation of enzalutamide. Patients taking hormonal replacement therapy may need to be monitored for reduced clinical effect while on enzalutamide, with dose adjustments made based on clinical efficacy. Higher-dose hormonal regimens may be indicated where acceptable or applicable. Women taking hormonal replacement and enzalutamide should report breakthrough bleeding, hot flashes, or other symptoms to their prescribers. Progestins are substrates of CYP3A4 and enzalutamide is a strong CYP3A4 inducer. Concurrent administration of enzalutamide with progestins, oral contraceptives, or non-oral combination contraceptives may reduce hormonal concentrations. This interaction does not apply to vaginal preparations of progesterone (e.g., Crinone, Endometrin).
Ertugliflozin: (Minor) Progestins can impair glucose tolerance. Patients receiving antidiabetic agents should be closely monitored for signs indicating changes in diabetic control when therapy with progestins is instituted or discontinued.
Ertugliflozin; Metformin: (Minor) Patients receiving antidiabetic agents like metformin should be closely monitored for signs indicating changes in diabetic control when therapy with progestins is instituted or discontinued. Progestins can impair glucose tolerance. (Minor) Progestins can impair glucose tolerance. Patients receiving antidiabetic agents should be closely monitored for signs indicating changes in diabetic control when therapy with progestins is instituted or discontinued.
Ertugliflozin; Sitagliptin: (Minor) Progestins can decrease the hypoglycemic effects of antidiabetic agents by impairing glucose tolerance. Patients receiving antidiabetic agents should be closely monitored for changes in diabetic control when hormone therapy is instituted or discontinued. (Minor) Progestins can impair glucose tolerance. Patients receiving antidiabetic agents should be closely monitored for signs indicating changes in diabetic control when therapy with progestins is instituted or discontinued.
Erythromycin: (Minor) The metabolism of progesterone may be inhibited by erythromycin, an inhibitor of cytochrome P450 3A4 hepatic enzymes.
Etravirine: (Major) Women taking both progestins and etravirine should report breakthrough bleeding to their prescribers. An alternate or additional form of contraception should be considered in patients prescribed etravirine. Higher-dose hormonal regimens may be indicated where acceptable or applicable. The alternative or additional contraceptive agent may need to be continued for one month after discontinuation of etravirine. For patients on hormone replacement treatments (HRT) with progestins, monitor for altered clinical response, such as increased hot flashes, vaginal dryness, changes in withdrawal bleeding, or other signs of decreased hormonal efficacy. Progestins are CYP3A4 substrates and etravirine is a strong CYP3A4 inducer.
Felbamate: (Major) Based on very limited data, it appears felbamate can accelerate the clearance of the estrogen component of some oral contraceptives. Patients who experience breakthrough bleeding while receiving these drugs together should notify their prescribers. An alternate or additional form of contraception should be used during concomitant treatment. Additionally, patients taking non-oral combination contraceptives or estrogens or progestins for hormone replacement therapy may also experience reduced clinical efficacy; dosage adjustments may be necessary.
Fluconazole: (Minor) The metabolism of progesterone may be inhibited by fluconazole, an inhibitor of cytochrome P450 3A4 hepatic enzymes.
Food: (Minor) Food can increase the bioavailability of progesterone administered orally.
Fosamprenavir: (Major) Avoid concurrent use of contraceptives and hormone replacement therapies (HRT) containing progestins with fosamprenavir. Alternative methods of non-hormonal contraception are recommended. Concomitant use may decrease the efficacy of both the progestin and fosamprenavir, which could lead to loss of virologic response and possible viral resistance. Additionally, there is an increased risk of transaminase elevations during concurrent use of progestins and fosamprenavir boosted with ritonavir.
Glimepiride: (Minor) Progestins can impair glucose tolerance. Patients receiving antidiabetic agents should be closely monitored for signs indicating changes in diabetic control when therapy with progestins is instituted or discontinued.
Glipizide: (Minor) Progestins can impair glucose tolerance. Patients receiving antidiabetic agents should be closely monitored for signs indicating changes in diabetic control when therapy with progestins is instituted or discontinued.
Glipizide; Metformin: (Minor) Patients receiving antidiabetic agents like metformin should be closely monitored for signs indicating changes in diabetic control when therapy with progestins is instituted or discontinued. Progestins can impair glucose tolerance. (Minor) Progestins can impair glucose tolerance. Patients receiving antidiabetic agents should be closely monitored for signs indicating changes in diabetic control when therapy with progestins is instituted or discontinued.
Glyburide: (Minor) Progestins can impair glucose tolerance. Patients receiving antidiabetic agents should be closely monitored for signs indicating changes in diabetic control when therapy with progestins is instituted or discontinued.
Glyburide; Metformin: (Minor) Patients receiving antidiabetic agents like metformin should be closely monitored for signs indicating changes in diabetic control when therapy with progestins is instituted or discontinued. Progestins can impair glucose tolerance. (Minor) Progestins can impair glucose tolerance. Patients receiving antidiabetic agents should be closely monitored for signs indicating changes in diabetic control when therapy with progestins is instituted or discontinued.
Grapefruit juice: (Moderate) Be alert for a possible interaction with oral or injectable progesterone. Grapefruit juice, a strong CYP3A inhibitor, may increase concentrations of progesterone, which may increase the risk of progestin-related side effects such as breast tenderness, headache, or altered vaginal bleeding patterns. Formal drug interaction studies have not been conducted; however, progesterone is metabolized primarily by hydroxylation via the CYP3A4 in vitro. Vaginal preparations of progesterone are not expected to interact.
Griseofulvin: (Major) The concurrent use of griseofulvin and oral contraceptives can reduce contraceptive efficacy and result in an unintended pregnancy and/or breakthrough bleeding. This risk is particularly serious because griseofulvin is contraindicated during pregnancy due to the risk of teratogenic and abortifacient effects. An alternate or additional form of contraception should be used during concomitant treatment and continued for 1 month after griseofulvin discontinuation. If these drugs are used together, counsel the patient about the risk of pregnancy and teratogenic effects, and instruct the patient to notify the prescriber if they experience breakthrough bleeding while receiving these drugs together. Additionally, patients taking non-oral combination contraceptives or progestins for hormone replacement therapy may also experience reduced clinical efficacy.
Hydantoins: (Major) Women taking both progestins and hydantoins should report breakthrough bleeding to their prescribers. If used for contraception, an alternate or additional form of non-hormonal contraception should be considered in patients prescribed hydantoins. Higher-dose hormonal regimens may be indicated where acceptable or applicable. The alternative or additional contraceptive agent may need to be continued for 1 month after discontinuation of hydantoins. Patients taking progestins for other indications may need to be monitored for reduced clinical effect while on hydantoins, with dose adjustments made based on clinical efficacy. Hydantoins are strong hepatic CYP450 inducers. Concurrent administration may increase progestin elimination This interaction does not apply to vaginal preparations of progesterone (e.g., Crinone, Endometrin).
Idelalisib: (Moderate) Use caution if coadministration of idelalisib with progesterone is necessary, as the systemic exposure of progesterone may be increased resulting in an increase in treatment-related adverse reactions. Idelalisib is a strong CYP3A4 inhibitor. Progesterone is metabolized primarily by hydroxylation via a CYP3A4. This interaction does not apply to vaginal preparations of progesterone (e.g., Crinone, Endometrin).
Indinavir: (Moderate) Indinavir decreases the metabolism of oral contraceptives and non-oral combination contraceptives; the AUC for ethinyl estradiol and norethindrone increased by 24+/-17% and 26+/-14%, respectively, when coadministered with indinavir. Women receiving hormonal contraceptives and anti-retroviral protease inhibitors (PIs), such as indinavir, should be instructed to report any breakthrough bleeding or other adverse effects to their prescribers. Because hormonal contraceptives do not protect against the transmission of HIV/AIDS and other sexually transmitted diseases, women who receive hormonal contraceptives with PIs should use an additional barrier method of contraception such as condoms. This interaction does not apply to vaginal preparations of progesterone (e.g., Crinone, Endometrin).
Insulins: (Minor) Progestins can decrease the hypoglycemic effects of antidiabetic agents by impairing glucose tolerance. Patients receiving antidiabetic agents should be closely monitored for changes in diabetic control when hormone therapy is instituted or discontinued.
Isoniazid, INH; Pyrazinamide, PZA; Rifampin: (Major) Women taking both progestins and rifampin should report breakthrough bleeding to their prescribers. An alternate or additional form of contraception should be considered in patients prescribed rifampin. Higher-dose hormonal regimens may be indicated where acceptable or applicable. The alternative or additional contraceptive agent may need to be continued for one month after discontinuation of rifampin. For patients on hormone replacement treatments (HRT) with progestins, monitor for altered clinical response, such as increased hot flashes, vaginal dryness, changes in withdrawal bleeding, or other signs of decreased hormonal efficacy. Progestins are CYP3A4 substrates and rifampin is a strong CYP3A4 inducer.
Isoniazid, INH; Rifampin: (Major) Women taking both progestins and rifampin should report breakthrough bleeding to their prescribers. An alternate or additional form of contraception should be considered in patients prescribed rifampin. Higher-dose hormonal regimens may be indicated where acceptable or applicable. The alternative or additional contraceptive agent may need to be continued for one month after discontinuation of rifampin. For patients on hormone replacement treatments (HRT) with progestins, monitor for altered clinical response, such as increased hot flashes, vaginal dryness, changes in withdrawal bleeding, or other signs of decreased hormonal efficacy. Progestins are CYP3A4 substrates and rifampin is a strong CYP3A4 inducer.
Itraconazole: (Moderate) Use caution if coadministration of itraconazole with progesterone is necessary, as the systemic exposure of progesterone may be increased resulting in an increase in treatment-related adverse reactions. Itraconazole is a strong CYP3A4 inhibitor. Progesterone is metabolized primarily by hydroxylation via a CYP3A4. This interaction does not apply to vaginal preparations of progesterone (e.g., Crinone, Endometrin).
Ketoconazole: (Moderate) Use caution if coadministration of ketoconazole with progesterone is necessary, as the systemic exposure of progesterone may be increased resulting in an increase in treatment-related adverse reactions. Ketoconazole is a strong CYP3A4 inhibitor. Progesterone is metabolized primarily by hydroxylation via a CYP3A4. This interaction does not apply to vaginal preparations of progesterone.
Lamotrigine: (Moderate) Patients taking progestin hormones for contraception may consider an alternate or additional form of contraception, such as nonhormonal and/or barrier methods, during and for at least 1 month after discontinuation of lamotrigine. Higher-dose hormonal regimens may also be considered. Patients taking these hormones for other indications may need to be monitored for reduced clinical effect while on lamotrigine with dose adjustments made based on clinical efficacy. The AUC and Cmax of levonorgestrel decreased by 19% and 12%, respectively, among 16 volunteers during concurrent use with lamotrigine 300 mg/day. Serum progesterone concentrations did not suggest ovulation, however, serum FSH, LH, and estradiol concentrations suggested some loss of suppression of the hypothalamic-pituitary-ovarian axis.
Lansoprazole; Amoxicillin; Clarithromycin: (Moderate) Use caution if coadministration of clarithromycin with progesterone is necessary, as the systemic exposure of progesterone may be increased resulting in an increase in treatment-related adverse reactions. Clarithromycin is a strong CYP3A4 inhibitor. Progesterone is metabolized primarily by hydroxylation via a CYP3A4. This interaction does not apply to vaginal preparations of progesterone (e.g., Crinone, Endometrin).
Lesinurad: (Major) Hormonal contraceptives, including combination oral contraceptives, non-oral combination contraceptives, and contraceptives containing only progestins. This includes injectable, transdermal, and implantable forms. Hormonal contraceptives may not be reliable when coadministered with lesinurad. Females should use additional, non-hormonal methods of contraception and not rely solely on hormonal contraceptive methods when taking lesinurad.
Lesinurad; Allopurinol: (Major) Hormonal contraceptives, including combination oral contraceptives, non-oral combination contraceptives, and contraceptives containing only progestins. This includes injectable, transdermal, and implantable forms. Hormonal contraceptives may not be reliable when coadministered with lesinurad. Females should use additional, non-hormonal methods of contraception and not rely solely on hormonal contraceptive methods when taking lesinurad.
Levoketoconazole: (Moderate) Use caution if coadministration of ketoconazole with progesterone is necessary, as the systemic exposure of progesterone may be increased resulting in an increase in treatment-related adverse reactions. Ketoconazole is a strong CYP3A4 inhibitor. Progesterone is metabolized primarily by hydroxylation via a CYP3A4. This interaction does not apply to vaginal preparations of progesterone.
Linagliptin: (Minor) Estrogens, progestins, or oral contraceptives can decrease the hypoglycemic effects of antidiabetic agents by impairing glucose tolerance. Changes in glucose tolerance occur more commonly in patients receiving > 50 mcg of ethinyl estradiol per day. The presence or absence of a concomitant progestin may influence the significance of this effect. Patients receiving antidiabetic agents, such as linagliptin, should be closely monitored for changes in diabetic control when hormone therapy is instituted or discontinued.
Linagliptin; Metformin: (Minor) Estrogens, progestins, or oral contraceptives can decrease the hypoglycemic effects of antidiabetic agents by impairing glucose tolerance. Changes in glucose tolerance occur more commonly in patients receiving > 50 mcg of ethinyl estradiol per day. The presence or absence of a concomitant progestin may influence the significance of this effect. Patients receiving antidiabetic agents, such as linagliptin, should be closely monitored for changes in diabetic control when hormone therapy is instituted or discontinued. (Minor) Patients receiving antidiabetic agents like metformin should be closely monitored for signs indicating changes in diabetic control when therapy with progestins is instituted or discontinued. Progestins can impair glucose tolerance.
Lopinavir; Ritonavir: (Moderate) Use caution if coadministration of ritonavir with progesterone is necessary, as the systemic exposure of progesterone may be increased resulting in an increase in treatment-related adverse reactions. Ritonavir is a strong CYP3A4 inhibitor. Progesterone is metabolized primarily by hydroxylation via a CYP3A4. This interaction does not apply to vaginal preparations of progesterone (e.g., Crinone, Endometrin).
Lorlatinib: (Major) Women taking both progestins and lorlatinib should report breakthrough bleeding to their prescribers. An alternate or additional form of contraception should be considered in patients prescribed lorlatinib. Higher-dose hormonal regimens may be indicated where acceptable or applicable. The alternative or additional contraceptive agent may need to be continued for 1 month after discontinuation of lorlatinib. For patients on hormone replacement treatments (HRT) with progestins, monitor for altered clinical response, such as increased hot flashes, vaginal dryness, changes in withdrawal bleeding, or other signs of decreased hormonal efficacy. Progestins are CYP3A4 substrates and lorlatinib is a moderate CYP3A4 inducer.
Meglitinides: (Minor) Progestins can impair glucose tolerance. Patients receiving antidiabetic agents should be closely monitored for signs indicating changes in diabetic control when therapy with progestins is instituted or discontinued.
Metformin: (Minor) Patients receiving antidiabetic agents like metformin should be closely monitored for signs indicating changes in diabetic control when therapy with progestins is instituted or discontinued. Progestins can impair glucose tolerance.
Metformin; Repaglinide: (Minor) Patients receiving antidiabetic agents like metformin should be closely monitored for signs indicating changes in diabetic control when therapy with progestins is instituted or discontinued. Progestins can impair glucose tolerance.
Metformin; Rosiglitazone: (Minor) Patients receiving antidiabetic agents like metformin should be closely monitored for signs indicating changes in diabetic control when therapy with progestins is instituted or discontinued. Progestins can impair glucose tolerance. (Minor) Progestins can impair glucose tolerance. Patients receiving antidiabetic agents should be closely monitored for signs indicating changes in diabetic control when therapy with progestins is instituted or discontinued.
Metformin; Saxagliptin: (Minor) Patients receiving antidiabetic agents like metformin should be closely monitored for signs indicating changes in diabetic control when therapy with progestins is instituted or discontinued. Progestins can impair glucose tolerance. (Minor) Progestins can decrease the hypoglycemic effects of antidiabetic agents by impairing glucose tolerance. Patients receiving antidiabetic agents should be closely monitored for changes in diabetic control when hormone therapy is instituted or discontinued.
Metformin; Sitagliptin: (Minor) Patients receiving antidiabetic agents like metformin should be closely monitored for signs indicating changes in diabetic control when therapy with progestins is instituted or discontinued. Progestins can impair glucose tolerance. (Minor) Progestins can decrease the hypoglycemic effects of antidiabetic agents by impairing glucose tolerance. Patients receiving antidiabetic agents should be closely monitored for changes in diabetic control when hormone therapy is instituted or discontinued.
Methohexital: (Moderate) Barbiturates can accelerate the hepatic clearance of progestins. For hormonal contraceptives, this interaction could result in unintended pregnancy or breakthrough bleeding. For patients regularly taking a barbiturate, an alternative or back-up method of contraception may be advisable to ensure contraceptive reliability during the use of the barbiturate, and for 1 month following the discontinuation of barbiturate use. The exception is the use of levonorgestrel progestin IUDs, which have not been reported to interact and appear to maintain reliable efficacy. Pregnancy has been reported during therapy with both estrogen- and/or progestin-based oral contraceptives in patients receiving barbiturates (e.g., phenobarbital). For patients taking progestins for other indications, like hormone replacement, monitor the patient for signs and symptoms of reduced therapeutic efficacy or need for dosage adjustment.
Miconazole: (Moderate) Vaginal preparations of progesterone (e.g., Crinone, Endometrin, and Prochieve) should not be used with other intravaginal products (e.g., vaginal antifungals, such as clotrimazole, miconazole nitrate, terconazole, or tioconazole vaginal) as concurrent use may alter progesterone release and absorption from the vagina. Separate the times of administration to avoid the interaction. The manufacturers of Crinone and Prochieve indicate that other intravaginal products can be used as long as 6 hours has lapsed either before or after vaginal administration of progesterone. Endometrin is generally not recommended for use with other vaginal products (e.g., antifungal products) as this may alter progesterone release and absorption from the vaginal insert and the potential for interaction has not been formally assessed; use other vaginal products if medically necessary, but be aware that the response to Endometrin may be altered.
Miconazole; Petrolatum; Zinc Oxide: (Moderate) Vaginal preparations of progesterone (e.g., Crinone, Endometrin, and Prochieve) should not be used with other intravaginal products (e.g., vaginal antifungals, such as clotrimazole, miconazole nitrate, terconazole, or tioconazole vaginal) as concurrent use may alter progesterone release and absorption from the vagina. Separate the times of administration to avoid the interaction. The manufacturers of Crinone and Prochieve indicate that other intravaginal products can be used as long as 6 hours has lapsed either before or after vaginal administration of progesterone. Endometrin is generally not recommended for use with other vaginal products (e.g., antifungal products) as this may alter progesterone release and absorption from the vaginal insert a

nd the potential for interaction has not been formally assessed; use other vaginal products if medically necessary, but be aware that the response to Endometrin may be altered.
Mifepristone: (Moderate) Use caution if coadministration of mifepristone with progesterone is necessary, as the systemic exposure of progesterone may be increased resulting in an increase in treatment-related adverse reactions. Mifepristone is a strong CYP3A4 inhibitor. Progesterone is metabolized primarily by hydroxylation via a CYP3A4. This interaction does not apply to vaginal preparations of progesterone.
Mitotane: (Moderate) Use caution if coadministration of mitotane with progesterone is necessary, as the systemic exposure of progesterone may be decreased resulting in reduced efficacy. Mitotane is a strong CYP3A4 inducer. Progesterone is metabolized primarily by hydroxylation via a CYP3A4. This interaction does not apply to vaginal preparations of progesterone (e.g., Crinone, Endometrin).
Mobocertinib: (Major) Women taking both progestins and mobocertinib should report breakthrough bleeding to their prescribers. An alternate or additional form of contraception should be considered in patients prescribed mobocertinib. Higher-dose hormonal regimens may be indicated where acceptable or applicable. The alternative or additional contraceptive agent may need to be continued for one month after discontinuation of mobocertinib. For patients on hormone replacement treatments (HRT) with progestins, monitor for altered clinical response, such as increased hot flashes, vaginal dryness, changes in withdrawal bleeding, or other signs of decreased hormonal efficacy. Progestins are CYP3A substrates and mobocertinib is a weak CYP3A inducer.
Modafinil: (Major) Modafinil may cause failure of oral contraceptives or hormonal contraceptive-containing implants or devices due to induction of CYP3A4 isoenzyme metabolism of the progestins in these products. An alternative method or an additional method of contraception should be utilized during modafinil therapy and continued for one month after modafinil discontinuation. If these drugs are used together, monitor patients for a decrease in clinical effects; patients should report breakthrough bleeding to their prescriber. Dosage adjustments may be necessary.
Nefazodone: (Moderate) Use caution if coadministration of nefazodone with progesterone is necessary, as the systemic exposure of progesterone may be increased resulting in an increase in treatment-related adverse reactions. Nefazodone is a strong CYP3A4 inhibitor. Progesterone is metabolized primarily by hydroxylation via a CYP3A4. This interaction does not apply to vaginal preparations of progesterone (e.g., Crinone, Endometrin).
Nelfinavir: (Major) Nelfinavir can increase or decrease the metabolism of progesterone. Coadministration with ethinyl estradiol; norethindrone results in a 47% decrease in ethinyl estradiol plasma concentrations and an 18% decrease in norethindrone plasma concentrations. Women receiving progesterone and anti-retroviral protease inhibitors (PIs), such as nelfinavir, should be instructed to report any breakthrough bleeding or other adverse effects to their prescribers. It may be prudent for women who receive hormonal contraceptives concurrently with PIs to use an additional method of contraception to protect against unwanted pregnancy. Additionally, because hormonal contraceptives do not protect against the transmission of HIV/AIDS and other sexually transmitted diseases, women who receive hormonal contraceptives concurrently with PIs should use an additional barrier method of contraception such as condoms. The metabolism of progesterone may also be inhibited by nelfinavir, a strong inhibitor of the CYP3A4 hepatic enzyme. For patients taking progestins for other indications, like hormone replacement, monitor the patient for signs and symptoms of excess hormones. This interaction does not apply to vaginal preparations of progesterone (e.g., Crinone, Endometrin).
Nevirapine: (Moderate) Nevirapine may decrease plasma concentrations of oral contraceptives and non-oral combination contraceptives (i.e., ethinyl estradiol and norethindrone). However, despite lower exposures, literature suggests that use of nevirapine has no effect on pregnancy rates among HIV-infected women on combined oral contraceptives. Thus, the manufacturer states that no dose adjustments are needed when these drugs are used for contraception in combination with nevirapine. When these oral contraceptives are used for hormone replacement and given with nevirapine, the therapeutic effect of the hormonal therapy should be monitored.
Nirmatrelvir; Ritonavir: (Moderate) Use caution if coadministration of ritonavir with progesterone is necessary, as the systemic exposure of progesterone may be increased resulting in an increase in treatment-related adverse reactions. Ritonavir is a strong CYP3A4 inhibitor. Progesterone is metabolized primarily by hydroxylation via a CYP3A4. This interaction does not apply to vaginal preparations of progesterone (e.g., Crinone, Endometrin).
Omaveloxolone: (Major) Advise patients taking progestin hormones for contraception to consider an alternate or additional form of contraception, such as nonhormonal and/or barrier methods, during and for at least 1 month following discontinuation of omaveloxolone. Higher-dose hormonal regimens may also be considered. Patients taking these hormones for other indications may need to be monitored for reduced clinical effect while on omaveloxolone, with dose adjustments made based on clinical response. Progestins are CYP3A substrates and omaveloxolone is a CYP3A inducer. Concurrent administration may increase progestin elimination.
Oxcarbazepine: (Major) Progestins are susceptible to drug interactions with hepatic enzyme inducing drugs such as oxcarbazepine. Concurrent administration of oxcarbazepine progestins may increase the hormone's elimination. A high percentage of breakthrough bleeding has been reported in the literature from the combined use of oxcarbazepine and oral contraceptives; the results of one study demonstrated that the mean AUC of ethinyl estradiol/levonorgestrel was decreased by 52% when coadministered with oxcarbazepine. Women taking both hormones and hepatic enzyme-inducing drugs should report breakthrough bleeding to their prescribers. If used for contraception, an alternate or additional form of contraception should be considered in patients prescribed hepatic enzyme inducing drugs, or higher-dose hormonal regimens may be indicated where acceptable or applicable as pregnancy has been reported in patients taking the hepatic enzyme inducing drug phenytoin concurrently with hormonal contraceptives. The alternative or additional contraceptive agent may need to be continued for 1 month after discontinuation of the interacting medication. Additionally, epileptic women taking both anticonvulsants and OCs may be at higher risk of folate deficiency secondary to additive effects on folate metabolism; if oral contraceptive failure occurs, the additive effects could potentially heighten the risk of neural tube defects in pregnancy. Patients taking these hormones for other indications may need to be monitored for reduced clinical effect while on oxcarbazepine, with dose adjustments made based on clinical efficacy.
Pentobarbital: (Moderate) Barbiturates can accelerate the hepatic clearance of progestins. For hormonal contraceptives, this interaction could result in unintended pregnancy or breakthrough bleeding. For patients regularly taking a barbiturate, an alternative or back-up method of contraception may be advisable to ensure contraceptive reliability during the use of the barbiturate, and for 1 month following the discontinuation of barbiturate use. The exception is the use of levonorgestrel progestin IUDs, which have not been reported to interact and appear to maintain reliable efficacy. Pregnancy has been reported during therapy with both estrogen- and/or progestin-based oral contraceptives in patients receiving barbiturates (e.g., phenobarbital). For patients taking progestins for other indications, like hormone replacement, monitor the patient for signs and symptoms of reduced therapeutic efficacy or need for dosage adjustment.
Phenobarbital: (Moderate) Barbiturates can accelerate the hepatic clearance of progestins. For hormonal contraceptives, this interaction could result in unintended pregnancy or breakthrough bleeding. For patients regularly taking a barbiturate, an alternative or back-up method of contraception may be advisable to ensure contraceptive reliability during the use of the barbiturate, and for 1 month following the discontinuation of barbiturate use. The exception is the use of levonorgestrel progestin IUDs, which have not been reported to interact and appear to maintain reliable efficacy. Pregnancy has been reported during therapy with both estrogen- and/or progestin-based oral contraceptives in patients receiving barbiturates (e.g., phenobarbital). For patients taking progestins for other indications, like hormone replacement, monitor the patient for signs and symptoms of reduced therapeutic efficacy or need for dosage adjustment.
Phenobarbital; Hyoscyamine; Atropine; Scopolamine: (Moderate) Barbiturates can accelerate the hepatic clearance of progestins. For hormonal contraceptives, this interaction could result in unintended pregnancy or breakthrough bleeding. For patients regularly taking a barbiturate, an alternative or back-up method of contraception may be advisable to ensure contraceptive reliability during the use of the barbiturate, and for 1 month following the discontinuation of barbiturate use. The exception is the use of levonorgestrel progestin IUDs, which have not been reported to interact and appear to maintain reliable efficacy. Pregnancy has been reported during therapy with both estrogen- and/or progestin-based oral contraceptives in patients receiving barbiturates (e.g., phenobarbital). For patients taking progestins for other indications, like hormone replacement, monitor the patient for signs and symptoms of reduced therapeutic efficacy or need for dosage adjustment.
Phentermine; Topiramate: (Moderate) Patients taking progestin hormones for contraception may consider an alternate or additional form of contraception, such as nonhormonal and/or barrier methods, during and for 1 month following discontinuation of topiramate. Higher-dose hormonal regimens may also be considered. Monitor patients taking these hormones for other indications for reduced clinical effect while on topiramate; adjust drug dosage as appropriate based on clinical response. Progestins are CYP3A substrates and topiramate is a CYP3A inducer. Pharmacokinetic drug interaction studies have generally shown minimal impact on progestin concentrations especially at topiramate doses of 200 mg/day or less.
Pioglitazone: (Minor) Progestins can impair glucose tolerance. Patients receiving antidiabetic agents should be closely monitored for signs indicating changes in diabetic control when therapy with progestins is instituted or discontinued.
Pioglitazone; Glimepiride: (Minor) Progestins can impair glucose tolerance. Patients receiving antidiabetic agents should be closely monitored for signs indicating changes in diabetic control when therapy with progestins is instituted or discontinued. (Minor) Progestins can impair glucose tolerance. Patients receiving antidiabetic agents should be closely monitored for signs indicating changes in diabetic control when therapy with progestins is instituted or discontinued.
Pioglitazone; Metformin: (Minor) Patients receiving antidiabetic agents like metformin should be closely monitored for signs indicating changes in diabetic control when therapy with progestins is instituted or discontinued. Progestins can impair glucose tolerance. (Minor) Progestins can impair glucose tolerance. Patients receiving antidiabetic agents should be closely monitored for signs indicating changes in diabetic control when therapy with progestins is instituted or discontinued.
Posaconazole: (Moderate) Use caution if coadministration of posaconazole with progesterone is necessary, as the systemic exposure of progesterone may be increased resulting in an increase in treatment-related adverse reactions. Posaconazole is a strong CYP3A4 inhibitor. Progesterone is metabolized primarily by hydroxylation via a CYP3A4. This interaction does not apply to vaginal preparations of progesterone (e.g., Crinone, Endometrin).
Pramlintide: (Minor) Progestins can impair glucose tolerance. Patients receiving antidiabetic agents should be closely monitored for signs indicating changes in diabetic control when therapy with progestins is instituted or discontinued.
Prasterone, Dehydroepiandrosterone, DHEA (Dietary Supplements): (Moderate) Either additive or antagonistic effects could potentially occur if prasterone is combined with progestins.
Prasterone, Dehydroepiandrosterone, DHEA (FDA-approved): (Moderate) Either additive or antagonistic effects could potentially occur if prasterone is combined with progestins.
Primidone: (Moderate) Barbiturates can accelerate the hepatic clearance of progestins. For hormonal contraceptives, this interaction could result in unintended pregnancy or breakthrough bleeding. For patients regularly taking a barbiturate, an alternative or back-up method of contraception may be advisable to ensure contraceptive reliability during the use of the barbiturate, and for 1 month following the discontinuation of barbiturate use. The exception is the use of levonorgestrel progestin IUDs, which have not been reported to interact and appear to maintain reliable efficacy. Pregnancy has been reported during therapy with both estrogen- and/or progestin-based oral contraceptives in patients receiving barbiturates (e.g., phenobarbital). For patients taking progestins for other indications, like hormone replacement, monitor the patient for signs and symptoms of reduced therapeutic efficacy or need for dosage adjustment.
Ribociclib: (Moderate) Use caution if coadministration of ribociclib with progesterone is necessary, as the systemic exposure of progesterone may be increased resulting in an increase in treatment-related adverse reactions. Ribociclib is a strong CYP3A4 inhibitor. Progesterone is metabolized primarily by hydroxylation via a CYP3A4. This interaction does not apply to vaginal preparations of progesterone (e.g., Crinone, Endometrin).
Ribociclib; Letrozole: (Moderate) Use caution if coadministration of ribociclib with progesterone is necessary, as the systemic exposure of progesterone may be increased resulting in an increase in treatment-related adverse reactions. Ribociclib is a strong CYP3A4 inhibitor. Progesterone is metabolized primarily by hydroxylation via a CYP3A4. This interaction does not apply to vaginal preparations of progesterone (e.g., Crinone, Endometrin).
Rifampin: (Major) Women taking both progestins and rifampin should report breakthrough bleeding to their prescribers. An alternate or additional form of contraception should be considered in patients prescribed rifampin. Higher-dose hormonal regimens may be indicated where acceptable or applicable. The alternative or additional contraceptive agent may need to be continued for one month after discontinuation of rifampin. For patients on hormone replacement treatments (HRT) with progestins, monitor for altered clinical response, such as increased hot flashes, vaginal dryness, changes in withdrawal bleeding, or other signs of decreased hormonal efficacy. Progestins are CYP3A4 substrates and rifampin is a strong CYP3A4 inducer.
Rifapentine: (Major) Women taking both progestins and rifapentine should report breakthrough bleeding to their prescribers. An alternate or additional form of contraception should be considered in patients prescribed rifapentine. Higher-dose hormonal regimens may be indicated where acceptable or applicable. The alternative or additional contraceptive agent may need to be continued for one month after discontinuation of rifapentine. For patients on hormone replacement treatments (HRT) with progestins, monitor for altered clinical response, such as increased hot flashes, vaginal dryness, changes in withdrawal bleeding, or other signs of decreased hormonal efficacy. Progestins are CYP3A4 substrates and rifapentine is a strong CYP3A4 inducer.
Ritonavir: (Moderate) Use caution if coadministration of ritonavir with progesterone is necessary, as the systemic exposure of progesterone may be increased resulting in an increase in treatment-related adverse reactions. Ritonavir is a strong CYP3A4 inhibitor. Progesterone is metabolized primarily by hydroxylation via a CYP3A4. This interaction does not apply to vaginal preparations of progesterone (e.g., Crinone, Endometrin).
Rosiglitazone: (Minor) Progestins can impair glucose tolerance. Patients receiving antidiabetic agents should be closely monitored for signs indicating changes in diabetic control when therapy with progestins is instituted or discontinued.
Saquinavir: (Moderate) Use caution if coadministration of saquinavir with progesterone is necessary, as the systemic exposure of progesterone may be increased resulting in an increase in treatment-related adverse reactions. Saquinavir is a strong CYP3A4 inhibitor. Progesterone is metabolized primarily by hydroxylation via a CYP3A4. This interaction does not apply to vaginal preparations of progesterone (e.g., Crinone, Endometrin).
Saxagliptin: (Minor) Progestins can decrease the hypoglycemic effects of antidiabetic agents by impairing glucose tolerance. Patients receiving antidiabetic agents should be closely monitored for changes in diabetic control when hormone therapy is instituted or discontinued.
Secobarbital: (Moderate) Barbiturates can accelerate the hepatic clearance of progestins. For hormonal contraceptives, this interaction could result in unintended pregnancy or breakthrough bleeding. For patients regularly taking a barbiturate, an alternative or back-up method of contraception may be advisable to ensure contraceptive reliability during the use of the barbiturate, and for 1 month following the discontinuation of barbiturate use. The exception is the use of levonorgestrel progestin IUDs, which have not been reported to interact and appear to maintain reliable efficacy. Pregnancy has been reported during therapy with both estrogen- and/or progestin-based oral contraceptives in patients receiving barbiturates (e.g., phenobarbital). For patients taking progestins for other indications, like hormone replacement, monitor the patient for signs and symptoms of reduced therapeutic efficacy or need for dosage adjustment.
Sincalide: (Moderate) Sincalide-induced gallbladder ejection fraction may be affected by concurrent progesterone. False study results are possible in patients with drug-induced hyper- or hypo-responsiveness; thorough patient history is important in the interpretation of procedure results.
Sitagliptin: (Minor) Progestins can decrease the hypoglycemic effects of antidiabetic agents by impairing glucose tolerance. Patients receiving antidiabetic agents should be closely monitored for changes in diabetic control when hormone therapy is instituted or discontinued.
Sodium Iodide: (Moderate) Progesterone is known to decrease the uptake of iodide into thyroid tissue. In order to increase thyroid uptake and optimize exposure of thyroid tissue to the radionucleotide sodium iodide I-131, consider withholding progesterone prior to treatment with sodium iodide I-131.
St. John's Wort, Hypericum perforatum: (Major) As with other CYP3A4 inducers, St. John's wort may reduce the therapeutic efficacy of progestin-only contraceptives or other progestin-based hormonal therapies. Patients should report irregular menstrual bleeding or other hormone-related symptoms to their health care providers if they are taking St. John's wort concurrently with their hormones. Avoidance of St. John's wort is recommended. This interaction does not apply to vaginal preparations of progesterone (e.g., Crinone, Endometrin).
Sulfonylureas: (Minor) Progestins can impair glucose tolerance. Patients receiving antidiabetic agents should be closely monitored for signs indicating changes in diabetic control when therapy with progestins is instituted or discontinued.
Tazemetostat: (Major) Women taking both progestins and tazemetostat should report breakthrough bleeding to their prescribers. An alternate or additional form of contraception should be considered in patients prescribed tazemetostat. Higher-dose hormonal regimens may be indicated where acceptable or applicable. The alternative or additional contraceptive agent may need to be continued for 1 month after discontinuation of tazemetostat. For patients on hormone replacement treatments (HRT) with progestins, monitor for altered clinical response, such as increased hot flashes, vaginal dryness, changes in withdrawal bleeding, or other signs of decreased hormonal efficacy. Progestins are CYP3A4 substrates and tazemetostat is a weak CYP3A4 inducer.
Thiazolidinediones: (Minor) Progestins can impair glucose tolerance. Patients receiving antidiabetic agents should be closely monitored for signs indicating changes in diabetic control when therapy with progestins is instituted or discontinued.
Tipranavir: (Major) Tipranavir can increase or decrease the metabolism of hormones. Concentrations of ethinyl estradiol decrease by 50% when coadministered. Additionally, in one drug interaction trial in healthy female volunteers administered a single dose of ethinyl estradiol followed by tipranavir with ritonavir, 33% of subjects developed a rash. Women receiving combined hormonal contraceptives and anti-retroviral protease inhibitors (PIs), such as tipranavir, should be instructed to report any breakthrough bleeding or other adverse effects to their prescribers. Alternate methods of non-hormonal contraception should be used in patients receiving tipranavir. Because hormonal contraceptives do not protect against the transmission of HIV/AIDS and other sexually transmitted diseases, women who receive hormonal contraceptives concurrently with PIs should use an additional barrier method of contraception such as condoms. The metabolism of progesterone may also be inhibited by tipranavir, a strong inhibitor of the CYP3A4 hepatic enzyme. For patients taking progestins for other indications, like hormone replacement, monitor the patient for signs and symptoms of excess hormones. This interaction does not apply to vaginal preparations of progesterone (e.g., Crinone, Endometrin).
Tolazamide: (Minor) Progestins can impair glucose tolerance. Patients receiving antidiabetic agents should be closely monitored for signs indicating changes in diabetic control when therapy with progestins is instituted or discontinued.
Tolbutamide: (Minor) Progestins can impair glucose tolerance. Patients receiving antidiabetic agents should be closely monitored for signs indicating changes in diabetic control when therapy with progestins is instituted or discontinued.
Topiramate: (Moderate) Patients taking progestin hormones for contraception may consider an alternate or additional form of contraception, such as nonhormonal and/or barrier methods, during and for 1 month following discontinuation of topiramate. Higher-dose hormonal regimens may also be considered. Monitor patients taking these hormones for other indications for reduced clinical effect while on topiramate; adjust drug dosage as appropriate based on clinical response. Progestins are CYP3A substrates and topiramate is a CYP3A inducer. Pharmacokinetic drug interaction studies have generally shown minimal impact on progestin concentrations especially at topiramate doses of 200 mg/day or less.
Trandolapril; Verapamil: (Minor) The metabolism of progesterone may be inhibited by verapamil, an inhibitor of cytochrome P450 3A4 hepatic enzymes.
Tucatinib: (Moderate) Use caution if coadministration of tucatinib with progesterone is necessary, as the systemic exposure of progesterone may be increased resulting in an increase in treatment-related adverse reactions. Tucatinib is a strong CYP3A4 inhibitor. Progesterone is metabolized primarily by hydroxylation via a CYP3A4. This interaction does not apply to vaginal preparations of progesterone (e.g., Crinone, Endometrin).
Ulipristal: (Major) Avoid concurrent use of ulipristal and progestin-containing hormonal contraceptives or other progestins. Hormonal contraceptives may be started or resumed no sooner than 5 days after ulipristal treatment. Also, a reliable barrier method of contraception should be used during the same menstrual cycle in which ulipristal was administered (until the next menstrual period). Progestin-containing contraceptives may impair the ability of ulipristal to delay ovulation. Ulipristal may reduce the effectiveness of progestin-containing hormonal contraceptives by competitively binding at the progesterone receptor.
Verapamil: (Minor) The metabolism of progesterone may be inhibited by verapamil, an inhibitor of cytochrome P450 3A4 hepatic enzymes.
Vonoprazan; Amoxicillin; Clarithromycin: (Moderate) Use caution if coadministration of clarithromycin with progesterone is necessary, as the systemic exposure of progesterone may be increased resulting in an increase in treatment-related adverse reactions. Clarithromycin is a strong CYP3A4 inhibitor. Progesterone is metabolized primarily by hydroxylation via a CYP3A4. This interaction does not apply to vaginal preparations of progesterone (e.g., Crinone, Endometrin).
Voriconazole: (Moderate) Use caution if coadministration of voriconazole with progesterone is necessary, as the systemic exposure of progesterone may be increased resulting in an increase in treatment-related adverse reactions. Voriconazole is a strong CYP3A4 inhibitor. Progesterone is metabolized primarily by hydroxylation via a CYP3A4. This interaction does not apply to vaginal preparations of progesterone (e.g., Crinone, Endometrin).

How Supplied

Crinone Vaginal Gel: 4%, 8%
Endometrin Vaginal Insert: 100mg
Progesterone Intramuscular Inj Sol: 1mL, 50mg
Progesterone/PROMETRIUM Oral Cap: 100mg, 200mg

Maximum Dosage
Adults

Dependent on indication for therapy, and dosage route/formulation selected.

Elderly

Dependent on indication for therapy, and dosage route/formulation selected.

Adolescents

Dependent on indication for therapy, and dosage route/formulation selected.

Children

Not indicated in prepubescent females.

Mechanism Of Action

Progesterone is a naturally occurring steroid that is secreted by the ovary, placenta, and adrenal gland. In the presence of adequate estrogen, progesterone transforms a proliferative endometrium into a secretory endometrium. Progesterone is essential for the development of decidual tissue, and the effect of progesterone on the differentiation of glandular epithelia and stroma has been extensively studied. Progesterone is necessary to increase endometrial receptivity for implantation of an embryo. Once an embryo is implanted, progesterone acts to maintain the pregnancy. Normal or near-normal endometrial responses to oral estradiol and intramuscular progesterone have been noted in functionally agonadal women through the sixth decade of life. Progesterone administration decreases the circulatory levels of gonadotropins.
 
Progesterone can be used to achieve normalized progesterone levels in women with secondary amenorrhea. When a woman does not produce enough progesterone, menstrual irregularities may occur. Progesterone can thus help re-establish normal menstrual cycles in pre-menopausal women with such irregularities.
 
The primary role of progesterone when used in the menopausal woman is for a protective effect that reductes the risk of endometrial hyperplasia when used with estrogen in the woman with an intact uterus. Micronized oral progesterone does not appear to have adverse effects on serum lipid profiles when used in regimens for hormone replacement therapy (HRT).
 
Progesterone has also been used historically as a contraceptive, including in intrauterine contraceptive devices (IUDs). The primary contraceptive effect of exogenous progestins involves the suppression of the midcycle surge of luteinizing hormone (LH). The exact mechanism of action, however, is unknown. At the cellular level, progestins diffuse freely into target cells and bind to the progesterone receptor. Target cells include the female reproductive tract, the mammary gland, the hypothalamus, and the pituitary. Once bound to the receptor, progestins slow the frequency of release of gonadotropin releasing hormone (GnRH) from the hypothalamus and blunt the pre-ovulatory LH surge, thereby preventing follicular maturation and ovulation. Additional mechanisms may be involved in the contraceptive effect. Other actions of progestins include alterations in the endometrium that can impair implantation and an increase in cervical mucus viscosity which inhibits sperm migration into the uterus.

Pharmacokinetics

Progesterone is administered orally (Prometrium micronized soft gelatin capsules), intramuscularly, intravaginally (Crinone gel, Prochieve gel), or as a component of an intrauterine device (IUD). Vaginal suppositories are also compounded for use, however, pharmacokinetic data is unavailable. Once in the systemic circulation, progesterone is extensively (96—99%) bound to cortisol binding globulin, sex hormone binding globulin, and albumin. The drug is metabolized hepatically to pregnanediol and conjugated with glucuronic acid. The plasma elimination half-life ranges 5—20 minutes. The metabolites are excreted primarily in the urine (50—60%). About 10% is eliminated via the bile and feces.

Oral Route

After oral administration, progesterone is significantly absorbed with peak serum concentration occurring within 3 hours. The absolute bioavailability, however, is not known.

Intramuscular Route

The absorption of progesterone following intramuscular injection is rapid, and the effects last for about 24 hours.

Other Route(s)

Vaginal Route
Following intravaginal administration of progesterone gel, absorption is prolonged with an absorption half-life of approximately 25—50 hours.
 
Intrauterine Route
Intrauterine devices release progesterone at an average rate of 65 mcg/day by membrane controlled diffusion. Local absorption of progesterone into the uterine epithelium readily occurs. Systemic absorption from an IUD is clinically insignificant.

Pregnancy And Lactation
Pregnancy

Detectable amounts of drug have been identified in the milk of mothers receiving progestational drugs. The effect of this on the breast-feeding infant has not been determined. In general, use of progestins has not had adverse effects on lactation. Consider the developmental and health benefits of breast-feeding along with the mother's clinical need for progesterone and the potential adverse effects on the breast-fed infant.