Primaquine

Antimalarials

Oral Administration

Primaquine is administered with food to decrease adverse GI effects.

Severe

hemolytic anemia / Delayed / Incidence not known
methemoglobinemia / Early / Incidence not known

Moderate

leukopenia / Delayed / Incidence not known
QT prolongation / Rapid / Incidence not known

Mild

vomiting / Early / Incidence not known
nausea / Early / Incidence not known
dizziness / Early / Incidence not known
rash / Early / Incidence not known
pruritus / Rapid / Incidence not known

Primaquine

Rx

Oral antimalarial agent; chemically related to chloroquine; not effective against asexual erythrocytic forms; alternative agent for PCP in combination with clindamycin.

For the radical cure (prevention of relapse) of malaria due to P. vivax or P. ovale† in patients who are receiving appropriate antimalarial therapy for acute infection. Oral dosage Adults weighing 70 kg or more

52.6 mg (30 mg base) PO once daily until cumulative dose of 10.52 mg/kg (6 mg/kg base). The FDA-approved dosage is 26.3 mg (15 mg base) PO once daily for 14 days. Give in combination with all regimens. For pregnant persons, administer after delivery.

Adults weighing 69 kg or less

52.6 mg (30 mg base) PO once daily for 14 days. The FDA-approved dosage is 26.3 mg (15 mg base) PO once daily for 14 days. Give in combination with all regimens. For pregnant persons, administer after delivery.

Adults with intermediate G6PD deficiency†

78.9 mg (45 mg base) PO once weekly for 8 weeks. Give in combination with all regimens.

Children† and Adolescents† weighing 70 kg or more

52.6 mg (30 mg base) PO once daily until cumulative dose of 10.52 mg/kg (6 mg/kg base). Give in combination with all regimens. For pregnant persons, administer after delivery.

Infants†, Children†, and Adolescents† weighing 69 kg or less

0.8 mg (0.5 mg base)/kg/dose [Max: 52.6 mg/dose (30 mg base/dose)] PO once daily for 14 days. Give in combination with all regimens. For pregnant persons, administer after delivery.

For malaria prophylaxis†. For presumptive antirelapse malaria prophylaxis† of either P. vivax or P. ovale malaria. Oral dosage Adults

52.6 mg (30 mg base) PO once daily for 14 days after leaving the endemic area. When chloroquine, doxycycline, or mefloquine is used for primary prophylaxis, administer primaquine during the last 2 weeks of prophylaxis. When atovaquone; proguanil is used for primary prophylaxis, administer primaquine during the last 7 days of prophylaxis and then for an additional 7 days.

Infants, Children, and Adolescents

0.8 mg (0.5 mg base)/kg/dose [Max: 52.6 mg/dose (30 mg base/dose)] PO once daily for 14 days after leaving the the endemic area. When chloroquine, doxycycline, or mefloquine is used for primary prophylaxis, administer primaquine during the last 2 weeks of prophylaxis. When atovaquone; proguanil is used for primary prophylaxis, administer primaquine during the last 7 days of prophylaxis and then for an additional 7 days.

For primary malaria prophylaxis†. Oral dosage Adults

52.6 mg (30 mg base) PO once daily, starting 1 to 2 days prior to entry into endemic area and continuing for 7 days after leaving the area. Primarily recommended in areas with P. vivax.

Infants, Children, and Adolescents

0.8 mg (0.5 mg base)/kg/dose [Max: 52.6 mg/dose (30 mg base/dose)] PO once daily, starting 1 to 2 days prior to entry into endemic area and continuing for 7 days after leaving the area. Primarily recommended in areas with P. vivax.

For the treatment of Pneumocystis pneumonia (PCP)†. For the treatment of PCP in HIV-infected patients†. Oral dosage Adults

52.6 mg (30 mg base) PO once daily in combination with clindamycin for 21 days as alternative therapy then chronic suppressive therapy.

Adolescents

52.6 mg (30 mg base) PO once daily in combination with clindamycin for 21 days as alternative therapy then chronic suppressive therapy.

Infants and Children

0.3 mg/kg/dose base (Max: 30 mg/dose base) PO once daily in combination with clindamycin for 21 days as alternative therapy then chronic suppressive therapy.

For the treatment of PCP in solid organ transplant recipients†. Oral dosage Adults

26.3 to 52.6 mg (15 to 30 mg base) PO once daily in combination with clindamycin for 14 to 21 days as alternative therapy.

For the treatment of PCP in patients with hematological malignancies, cancer, or autoimmune/inflammatory disease. Oral dosage Adults

52.6 mg (30 mg base) PO once daily in combination with clindamycin for 14 to 21 days as alternative therapy.

Infants, Children, and Adolescents

0.3 mg/kg/dose base (Max: 30 mg/dose base) PO once daily in combination with clindamycin for 14 to 21 days as alternative therapy.

†Indicates off-label use

Hepatic Impairment

Specific guidelines for dosage adjustments in hepatic impairment are not available; however primaquine is extensively metabolized by the liver. Use with caution in patients with hepatic impairment.

Renal Impairment

Specific guidelines for dosage adjustments in renal impairment are not available; it appears that dosage adjustments are not necessary.

Adagrasib: (Major) Concomitant use of adagrasib and primaquine increases the risk of QT/QTc prolongation and torsade de pointes (TdP). Avoid concomitant use if possible, especially in patients with additional risk factors for TdP. Consider taking steps to minimize the risk for QT/QTc interval prolongation and TdP, such as electrolyte monitoring and repletion and ECG monitoring, if concomitant use is necessary.
Alfuzosin: (Moderate) Use caution when administering alfuzosin with primaquine due to the potential for QT prolongation. Alfuzosin may prolong the QT interval in a dose-dependent manner. Primaquine also has the potential to prolong the QT interval.
Amiodarone: (Major) Concomitant use of primaquine and amiodarone increases the risk of QT/QTc prolongation and torsade de pointes (TdP). Avoid concomitant use if possible, especially in patients with additional risk factors for TdP. Consider taking steps to minimize the risk for QT/QTc interval prolongation and TdP, such as electrolyte monitoring and repletion and ECG monitoring, if concomitant use is necessary. Due to the extremely long half-life of amiodarone, a drug interaction is possible for days to weeks after drug discontinuation.
Amisulpride: (Major) Monitor ECGs for QT prolongation when amisulpride is administered with primaquine. Amisulpride causes dose- and concentration- dependent QT prolongation. Primaquine has the potential to prolong the QT interval.
Amoxicillin; Clarithromycin; Omeprazole: (Major) Due to the potential for QT interval prolongation with primaquine, caution is advised with other drugs that prolong the QT interval. Drugs with a possible risk for QT prolongation and TdP that should be used cautiously and with close monitoring with primaquine include clarithromycin.
Anagrelide: (Major) Due to the potential for QT interval prolongation with primaquine, caution is advised with other drugs that prolong the QT interval. Drugs with a possible risk for QT prolongation and TdP that should be used cautiously and with close monitoring with primaquine include anagrelide.
Apomorphine: (Moderate) Exercise caution when administering apomorphine concomitantly with primaquine since concurrent use may increase the risk of QT prolongation. Primaquine has the potential to prolong the QT interval. Dose-related QTc prolongation is associated with therapeutic apomorphine exposure.
Aripiprazole: (Moderate) Concomitant use of aripiprazole and primaquine may increase the risk of QT/QTc prolongation and torsade de pointes (TdP) in some patients. Consider taking steps to minimize the risk of QT/QTc interval prolongation and TdP, such as avoidance, electrolyte monitoring and repletion, and ECG monitoring, especially in patients with additional risk factors for TdP.
Arsenic Trioxide: (Major) Due to the potential for QT interval prolongation with primaquine, caution is advised with other drugs that prolong the QT interval. Drugs with a possible risk for QT prolongation and TdP that should be used cautiously and with close monitoring with primaquine include arsenic trioxide.
Artemether; Lumefantrine: (Major) Due to the potential for QT interval prolongation with primaquine, caution is advised with other drugs that prolong the QT interval. Drugs with a possible risk for QT prolongation and TdP that should be used cautiously and with close monitoring with primaquine include artemether; lumefantrine. (Moderate) Other antimalarial agents, such as primaquine, should not be given with artemether unless there is no other treatment option because limited safety data are available.
Articaine; Epinephrine: (Moderate) Coadministration of articaine with oxidizing agents, such as primaquine, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue articaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Asenapine: (Major) Due to the potential for QT interval prolongation with primaquine, caution is advised with other drugs that prolong the QT interval. Drugs with a possible risk for QT prolongation and TdP that should be used cautiously and with close monitoring with primaquine include asenapine.
Atomoxetine: (Moderate) Concomitant use of atomoxetine and primaquine may increase the risk of QT/QTc prolongation and torsade de pointes (TdP) in some patients. Consider taking steps to minimize the risk of QT/QTc interval prolongation and TdP, such as avoidance, electrolyte monitoring and repletion, and ECG monitoring, especially in patients with additional risk factors for TdP.
Azithromycin: (Major) Concomitant use of primaquine and azithromycin increases the risk of QT/QTc prolongation and torsade de pointes (TdP). Avoid concomitant use if possible, especially in patients with additional risk factors for TdP. Consider taking steps to minimize the risk for QT/QTc interval prolongation and TdP, such as electrolyte monitoring and repletion and ECG monitoring, if concomitant use is necessary.
Bedaquiline: (Major) Due to the potential for QT interval prolongation with primaquine, caution is advised with other drugs that prolong the QT interval. Drugs with a possible risk for QT prolongation and TdP that should be used cautiously and with close monitoring with primaquine include bedaquiline.
Bismuth Subcitrate Potassium; Metronidazole; Tetracycline: (Moderate) Concomitant use of metronidazole and primaquine may increase the risk of QT/QTc prolongation and torsade de pointes (TdP) in some patients. Consider taking steps to minimize the risk of QT/QTc interval prolongation and TdP, such as avoidance, electrolyte monitoring and repletion, and ECG monitoring, especially in patients with additional risk factors for TdP.
Bismuth Subsalicylate; Metronidazole; Tetracycline: (Moderate) Concomitant use of metronidazole and primaquine may increase the risk of QT/QTc prolongation and torsade de pointes (TdP) in some patients. Consider taking steps to minimize the risk of QT/QTc interval prolongation and TdP, such as avoidance, electrolyte monitoring and repletion, and ECG monitoring, especially in patients with additional risk factors for TdP.
Bupivacaine Liposomal: (Moderate) Coadministration of bupivacaine with oxidizing agents, such as primaquine, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue bupivacaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Bupivacaine: (Moderate) Coadministration of bupivacaine with oxidizing agents, such as primaquine, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue bupivacaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Bupivacaine; Epinephrine: (Moderate) Coadministration of bupivacaine with oxidizing agents, such as primaquine, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue bupivacaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Bupivacaine; Lidocaine: (Moderate) Coadministration of bupivacaine with oxidizing agents, such as primaquine, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue bupivacaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) Coadministration of lidocaine with oxidizing agents, such as primaquine, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue lidocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Bupivacaine; Meloxicam: (Moderate) Coadministration of bupivacaine with oxidizing agents, such as primaquine, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue bupivacaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Buprenorphine: (Major) Concomitant use of primaquine and buprenorphine increases the risk of QT/QTc prolongation and torsade de pointes (TdP). Avoid concomitant use if possible, especially in patients with additional risk factors for TdP. Consider taking steps to minimize the risk for QT/QTc interval prolongation and TdP, such as electrolyte monitoring and repletion and ECG monitoring, if concomitant use is necessary.
Buprenorphine; Naloxone: (Major) Concomitant use of primaquine and buprenorphine increases the risk of QT/QTc prolongation and torsade de pointes (TdP). Avoid concomitant use if possible, especially in patients with additional risk factors for TdP. Consider taking steps to minimize the risk for QT/QTc interval prolongation and TdP, such as electrolyte monitoring and repletion and ECG monitoring, if concomitant use is necessary.
Cabotegravir; Rilpivirine: (Moderate) Exercise caution when administering primaquine in combination with rilpivirine as concurrent use may increase the risk of QT prolongation. Primaquine is associated with QT prolongation. Supratherapeutic doses of rilpivirine (75 to 300 mg/day) have caused QT prolongation.
Ceritinib: (Major) Avoid coadministration of ceritinib with primaquine if possible due to the risk of QT prolongation. If concomitant use is unavoidable, periodically monitor ECGs and electrolytes; an interruption of ceritinib therapy, dose reduction, or discontinuation of therapy may be necessary if QT prolongation occurs. Ceritinib causes concentration-dependent prolongation of the QT interval. Primaquine is also associated with QT prolongation.
Chloroprocaine: (Moderate) Coadministration of chloroprocaine with oxidizing agents, such as primaquine, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue chloroprocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Chloroquine: (Major) Avoid coadministration of chloroquine with primaquine due to the increased risk of QT prolongation or other toxicities. If use together is necessary, obtain an ECG at baseline to assess initial QT interval and determine frequency of subsequent ECG monitoring, avoid any non-essential QT prolonging drugs, and correct electrolyte imbalances. Chloroquine is associated with an increased risk of QT prolongation and torsade de pointes (TdP); the risk of QT prolongation is increased with higher chloroquine doses. Primaquine may also prolong the QT interval.
Chlorpromazine: (Major) Due to the potential for QT interval prolongation with primaquine, caution is advised with other drugs that prolong the QT interval. Drugs with a possible risk for QT prolongation and TdP that should be used cautiously and with close monitoring with primaquine include chlorpromazine.
Ciprofloxacin: (Moderate) Concomitant use of ciprofloxacin and primaquine may increase the risk of QT/QTc prolongation and torsade de pointes (TdP) in some patients. Consider taking steps to minimize the risk of QT/QTc interval prolongation and TdP, such as avoidance, electrolyte monitoring and repletion, and ECG monitoring, especially in patients with additional risk factors for TdP.
Cisapride: (Contraindicated) Primaquine has the potential to prolong the QT interval. QT prolongation and ventricular arrhythmias, including torsade de pointes (TdP) and death, have been reported with cisapride. Because of the potential for TdP, use of primaquine with cisapride is contraindicated.
Citalopram: (Major) Concomitant use of primaquine and citalopram increases the risk of QT/QTc prolongation and torsade de pointes (TdP). Avoid concomitant use if possible, especially in patients with additional risk factors for TdP. Consider taking steps to minimize the risk for QT/QTc interval prolongation and TdP, such as electrolyte monitoring and repletion and ECG monitoring, if concomitant use is necessary.
Clarithromycin: (Major) Due to the potential for QT interval prolongation with primaquine, caution is advised with other drugs that prolong the QT interval. Drugs with a possible risk for QT prolongation and TdP that should be used cautiously and with close monitoring with primaquine include clarithromycin.
Clofazimine: (Moderate) Concomitant use of clofazimine and primaquine may increase the risk of QT/QTc prolongation and torsade de pointes (TdP) in some patients. Consider taking steps to minimize the risk of QT/QTc interval prolongation and TdP, such as avoidance, electrolyte monitoring and repletion, and ECG monitoring, especially in patients with additional risk factors for TdP.
Clozapine: (Moderate) Exercise caution when administering primaquine in combination with clozapine as concurrent use may increase the risk of QT prolongation. Primaquine is associated with QT prolongation. Treatment with clozapine has been associated with QT prolongation, torsade de pointes (TdP), cardiac arrest, and sudden death.
Codeine; Phenylephrine; Promethazine: (Moderate) Concomitant use of promethazine and primaquine may increase the risk of QT/QTc prolongation and torsade de pointes (TdP) in some patients. Consider taking steps to minimize the risk of QT/QTc interval prolongation and TdP, such as avoidance, electrolyte monitoring and repletion, and ECG monitoring, especially in patients with additional risk factors for TdP.
Codeine; Promethazine: (Moderate) Concomitant use of promethazine and primaquine may increase the risk of QT/QTc prolongation and torsade de pointes (TdP) in some patients. Consider taking steps to minimize the risk of QT/QTc interval prolongation and TdP, such as avoidance, electrolyte monitoring and repletion, and ECG monitoring, especially in patients with additional risk factors for TdP.
Crizotinib: (Major) Avoid coadministration of crizotinib with primaquine due to the risk of QT prolongation. If concomitant use is unavoidable, monitor ECGs for QT prolongation and monitor electrolytes. An interruption of therapy, dose reduction, or discontinuation of therapy may be necessary for crizotinib if QT prolongation occurs. Crizotinib has been associated with concentration-dependent QT prolongation. Primaquine may also cause QT interval prolongation.
Dapsone: (Moderate) Coadministration of dapsone with primaquine may increase the risk of developing methemoglobinemia. Advise patients to discontinue treatment and seek immediate medical attention with any signs or symptoms of methemoglobinemia.
Dasatinib: (Moderate) Due to increased risk of QT prolongation, use dasatinib with caution in combination with primaquine. Both drugs have the potential to prolong the QT interval.
Degarelix: (Moderate) Consider whether the benefits of androgen deprivation therapy outweigh the potential risks in patients receiving primaquine as concurrent use may increase the risk of QT prolongation. Androgen deprivation therapy (i.e., degarelix) may prolong the QT/QTc interval. Primaquine is associated with QT prolongation.
Desflurane: (Major) Due to the potential for QT interval prolongation with primaquine, caution is advised with other drugs that prolong the QT interval. Drugs with a possible risk for QT prolongation and TdP that should be used cautiously and with close monitoring with primaquine include halogenated anesthetics.
Deutetrabenazine: (Moderate) Due to the potential for QT interval prolongation with primaquine, caution is advised with other drugs that prolong the QT interval. Deutetrabenazine may prolong the QT interval, but the degree of QT prolongation is not clinically significant when deutetrabenazine is administered within the recommended dosage range.
Dexmedetomidine: (Moderate) Concomitant use of dexmedetomidine and primaquine may increase the risk of QT/QTc prolongation and torsade de pointes (TdP) in some patients. Consider taking steps to minimize the risk of QT/QTc interval prolongation and TdP, such as avoidance, electrolyte monitoring and repletion, and ECG monitoring, especially in patients with additional risk factors for TdP.
Dextromethorphan; Quinidine: (Major) Due to the potential for QT interval prolongation with primaquine, caution is advised with other drugs that prolong the QT interval. Drugs with a possible risk for QT prolongation and TdP that should be used cautiously and with close monitoring with primaquine include quinidine.
Disopyramide: (Major) Due to the potential for QT interval prolongation with primaquine, caution is advised with other drugs that prolong the QT interval. Drugs with a possible risk for QT prolongation and TdP that should be used cautiously and with close monitoring with primaquine include disopyramide.
Dofetilide: (Major) Coadministration of dofetilide and primaquine is not recommended as concurrent use may increase the risk of QT prolongation. Dofetilide, a Class III antiarrhythmic agent, is associated with a well-established risk of QT prolongation and torsade de pointes (TdP). Primaquine has been associated with QT prolongation.
Dolasetron: (Moderate) Administer dolasetron with caution in combination with primaquine as concurrent use may increase the risk of QT prolongation. Primaquine has the potential for QT prolongation. Dolasetron has been associated with a dose-dependent prolongation in the QT, PR, and QRS intervals on an electrocardiogram.
Dolutegravir; Rilpivirine: (Moderate) Exercise caution when administering primaquine in combination with rilpivirine as concurrent use may increase the risk of QT prolongation. Primaquine is associated with QT prolongation. Supratherapeutic doses of rilpivirine (75 to 300 mg/day) have caused QT prolongation.
Donepezil: (Moderate) Use donepezil with caution in combination with primaquine as concurrent use may increase the risk of QT prolongation. Case reports indicate that QT prolongation and torsade de pointes (TdP) can occur during donepezil therapy. Primaquine may cause QT prolongation.
Donepezil; Memantine: (Moderate) Use donepezil with caution in combination with primaquine as concurrent use may increase the risk of QT prolongation. Case reports indicate that QT prolongation and torsade de pointes (TdP) can occur during donepezil therapy. Primaquine may cause QT prolongation.
Dronedarone: (Contraindicated) Primaquine has the potential to prolong the QT interval. Dronedarone administration is associated with a dose-related increase in the QTc interval. The increase in QTc is approximately 10 milliseconds at doses of 400 mg twice daily (the FDA-approved dose) and up to 25 milliseconds at doses of 1600 mg twice daily. Although there are no studies examining the effects of dronedarone in patients receiving other QT prolonging drugs, coadministration of such drugs may result in additive QT prolongation. Because of the potential for TdP, use of primaquine with dronedarone is contraindicated.
Droperidol: (Major) Due to the potential for QT interval prolongation with primaquine, caution is advised with other drugs that prolong the QT interval. Drugs with a possible risk for QT prolongation and TdP that should be used cautiously and with close monitoring with primaquine include droperidol.
Efavirenz: (Moderate) Consider alternatives to efavirenz when coadministering with primaquine. QT prolongation has been observed with use of both efavirenz and primaquine.
Efavirenz; Emtricitabine; Tenofovir Disoproxil Fumarate: (Moderate) Consider alternatives to efavirenz when coadministering with primaquine. QT prolongation has been observed with use of both efavirenz and primaquine.
Efavirenz; Lamivudine; Tenofovir Disoproxil Fumarate: (Moderate) Consider alternatives to efavirenz when coadministering with primaquine. QT prolongation has been observed with use of both efavirenz and primaquine.
Eliglustat: (Moderate) Exercise caution when administering primaquine in combination with eliglustat as concurrent use may increase the risk of QT prolongation. Primaquine is associated with QT prolongation. Eliglustat is predicted to cause PR, QRS, and/or QT prolongation at significantly elevated plasma concentrations.
Emtricitabine; Rilpivirine; Tenofovir alafenamide: (Moderate) Exercise caution when administering primaquine in combination with rilpivirine as concurrent use may increase the risk of QT prolongation. Primaquine is associated with QT prolongation. Supratherapeutic doses of rilpivirine (75 to 300 mg/day) have caused QT prolongation.
Emtricitabine; Rilpivirine; Tenofovir Disoproxil Fumarate: (Moderate) Exercise caution when administering primaquine in combination with rilpivirine as concurrent use may increase the risk of QT prolongation. Primaquine is associated with QT prolongation. Supratherapeutic doses of rilpivirine (75 to 300 mg/day) have caused QT prolongation.
Encorafenib: (Major) Avoid coadministration of encorafenib and primaquine due to the potential for additive QT prolongation. If concurrent use cannot be avoided, monitor ECGs for QT prolongation and monitor electrolytes; correct hypokalemia and hypomagnesemia prior to treatment. Encorafenib is associated with dose-dependent prolongation of the QT interval. Primaquine has also been associated with QT interval prolongation.
Entrectinib: (Major) Avoid coadministration of entrectinib with primaquine due to the risk of QT prolongation. Both entrectinib and primaquine have been associated with QT prolongation.
Eribulin: (Major) Due to the potential for QT interval prolongation with primaquine, caution is advised with other drugs that prolong the QT interval. Drugs with a possible risk for QT prolongation and TdP that should be used cautiously and with close monitoring with primaquine include eribulin.
Erythromycin: (Major) Concomitant use of primaquine and erythromycin increases the risk of QT/QTc prolongation and torsade de pointes (TdP). Avoid concomitant use if possible, especially in patients with additional risk factors for TdP. Consider taking steps to minimize the risk for QT/QTc interval prolongation and TdP, such as electrolyte monitoring and repletion and ECG monitoring, if concomitant use is necessary.
Escitalopram: (Moderate) Concomitant use of escitalopram and primaquine may increase the risk of QT/QTc prolongation and torsade de pointes (TdP) in some patients. Consider taking steps to minimize the risk of QT/QTc interval prolongation and TdP, such as avoidance, electrolyte monitoring and repletion, and ECG monitoring, especially in patients with additional risk factors for TdP.
Fingolimod: (Moderate) Due to the potential for QT interval prolongation with primaquine, caution is advised with other drugs that prolong the QT interval, such as fingolimod. Fingolimod initiation results in decreased heart rate and may prolong the QT interval. Fingolimod has not been studied in patients treated with drugs that prolong the QT interval, but drugs that prolong the QT interval have been associated with cases of TdP in patients with bradycardia.
Flecainide: (Major) Concomitant use of primaquine and flecainide increases the risk of QT/QTc prolongation and torsade de pointes (TdP). Avoid concomitant use if possible, especially in patients with additional risk factors for TdP. Consider taking steps to minimize the risk for QT/QTc interval prolongation and TdP, such as electrolyte monitoring and repletion and ECG monitoring, if concomitant use is necessary.
Fluconazole: (Moderate) Concomitant use of fluconazole and primaquine may increase the risk of QT/QTc prolongation and torsade de pointes (TdP) in some patients. Consider taking steps to minimize the risk of QT/QTc interval prolongation and TdP, such as avoidance, electrolyte monitoring and repletion, and ECG monitoring, especially in patients with additional risk factors for TdP.
Fluoxetine: (Moderate) Concomitant use of fluoxetine and primaquine may increase the risk of QT/QTc prolongation and torsade de pointes (TdP) in some patients. Consider taking steps to minimize the risk of QT/QTc interval prolongation and TdP, such as avoidance, electrolyte monitoring and repletion, and ECG monitoring, especially in patients with additional risk factors for TdP.
Fluphenazine: (Minor) Exercise caution when administering primaquine in combination with fluphenazine as concurrent use may increase the risk of QT prolongation. Fluphenazine is associated with a possible risk for QT prolongation. Theoretically, this phenothiazine may increase the risk of QT prolongation if coadministered with drugs with a risk of QT prolongation.
Fluvoxamine: (Moderate) Exercise caution when administering primaquine in combination with fluvoxamine as concurrent use may increase the risk of QT prolongation. Primaquine is associated with QT prolongation. QT prolongation and torsade de pointes (TdP) has been reported during fluvoxamine post-marketing use.
Food: (Moderate) Overall, the mean bioavailability of primaquine is increased by administration with food; the increase is not thought to be clinically harmful and may contribute to antimalarial efficacy. Administration with food is often recommended to limit GI intolerance.
Foscarnet: (Major) When possible, avoid concurrent use of foscarnet with other drugs known to prolong the QT interval, such as primaquine. Foscarnet has been associated with postmarketing reports of both QT prolongation and torsade de pointes (TdP). Primaquine may also prolong the QT interval. If these drugs are administered together, obtain an electrocardiogram and electrolyte concentrations before and periodically during treatment.
Fostemsavir: (Moderate) Due to the potential for QT interval prolongation with primaquine, caution is advised with other drugs that prolong the QT interval such as fostemsavir. Supratherapeutic doses of fostemsavir (2,400 mg twice daily, four times the recommended daily dose) have been shown to cause QT prolongation. Fostemsavir causes dose-dependent QT prolongation.
Gemifloxacin: (Moderate) Exercise caution when administering primaquine in combination with gemifloxacin as concurrent use may increase the risk of QT prolongation. Primaquine is associated with QT prolongation. Gemifloxacin may prolong the QT interval in some patients. The maximal change in the QTc interval occurs approximately 5 to 10 hours following oral administration of gemifloxacin. The likelihood of QTc prolongation may increase with increasing dose of the drug; therefore, the recommended dose should not be exceeded especially in patients with renal or hepatic impairment where the Cmax and AUC are slightly higher.
Gemtuzumab Ozogamicin: (Moderate) Use gemtuzumab ozogamicin and primaquine together with caution due to the potential for additive QT interval prolongation and risk of torsade de pointes (TdP). If these agents are used together, obtain an ECG and serum electrolytes prior to the start of gemtuzumab and as needed during treatment. Although QT interval prolongation has not been reported with gemtuzumab, it has been reported with other drugs that contain calicheamicin. Primaquine may prolong the QT interval.
Gilteritinib: (Moderate) Use caution and monitor for additive QT prolongation if concurrent use of gilteritinib and primaquine is necessary. Both drugs have been associated with QT prolongation.
Glasdegib: (Major) Avoid coadministration of glasdegib with primaquine due to the potential for additive QT prolongation. If coadministration cannot be avoided, monitor patients for increased risk of QT prolongation with increased frequency of ECG monitoring. Glasdegib therapy may result in QT prolongation and ventricular arrhythmias including ventricular fibrillation and ventricular tachycardia. Primaquine also has the potential to prolong the QT interval.
Goserelin: (Moderate) Consider whether the benefits of androgen deprivation therapy (i.e., goserelin) outweigh the potential risks of QT prolongation in patients receiving primaquine as concurrent use may increase the risk of QT prolongation. Primaquine has the potential to cause QT prolongation. Androgen deprivation therapy may also prolong the QT/QTc interval.
Granisetron: (Moderate) Use granisetron with caution in combination with primaquine due to increased risk for QT prolongation.
Grapefruit juice: (Moderate) Administration of primaquine with grapefruit juice requires caution. The metabolism of primaquine may be reduced when taken with grapefruit juice. In healthy subjects, grapefruit juice increased the mean Cmax of primaquine by 23% and the AUC by 19%; however, there was significant interindividual variability in the results. The authors of the study suggest avoidance of grapefruit juice during primaquine therapy. Alternatively, significant alterations in grapefruit juice intake should be avoided as a precaution during primaquine treatment.
Halogenated Anesthetics: (Major) Due to the potential for QT interval prolongation with primaquine, caution is advised with other drugs that prolong the QT interval. Drugs with a possible risk for QT prolongation and TdP that should be used cautiously and with close monitoring with primaquine include halogenated anesthetics.
Haloperidol: (Moderate) Due to the potential for QT interval prolongation with primaquine, caution is advised with haloperidol. Drugs with a possible risk for QT prolongation and TdP that should be used cautiously and with close monitoring with primaquine include haloperidol. QT prolongation and torsade de pointes (TdP) have been observed during haloperidol treatment. Excessive doses (particularly in the overdose setting) or IV administration of haloperidol may be associated with a higher risk of QT prolongation.
Histrelin: (Moderate) Consider whether the benefits of androgen deprivation therapy (i.e., histrelin) outweigh the potential risks of QT prolongation in patients receiving primaquine as concurrent use may increase the risk of QT prolongation. Primaquine has the potential to cause QT prolongation. Androgen deprivation therapy may also prolong the QT/QTc interval.
Hydroxychloroquine: (Major) Concomitant use of primaquine and hydroxychloroquine increases the risk of QT/QTc prolongation and torsade de pointes (TdP). Avoid concomitant use if possible, especially in patients with additional risk factors for TdP. Consider taking steps to minimize the risk for QT/QTc interval prolongation and TdP, such as electrolyte monitoring and repletion and ECG monitoring, if concomitant use is necessary.
Hydroxyzine: (Moderate) Concomitant use of hydroxyzine and primaquine may increase the risk of QT/QTc prolongation and torsade de pointes (TdP) in some patients. Consider taking steps to minimize the risk of QT/QTc interval prolongation and TdP, such as avoidance, electrolyte monitoring and repletion, and ECG monitoring, especially in patients with additional risk factors for TdP.
Ibutilide: (Major) Due to the potential for QT interval prolongation with primaquine, caution is advised with other drugs that prolong the QT interval. Drugs with a possible risk for QT prolongation and TdP that should be used cautiously and with close monitoring with primaquine include ibutilide.
Iloperidone: (Major) Due to the potential for QT interval prolongation with primaquine, caution is advised with other drugs that prolong the QT interval. Drugs with a possible risk for QT prolongation and TdP that should be used cautiously and with close monitoring with primaquine include iloperidone.
Inotuzumab Ozogamicin: (Major) Avoid coadministration of inotuzumab ozogamicin with primaquine in due to the potential for additive QT prolongation and risk of torsade de pointes (TdP). If coadministration is unavoidable, obtain an ECG and serum electrolytes prior to the start of treatment, after treatment initiation, and periodically during treatment. Both inotuzumab and primaquine have been associated with QT interval prolongation.
Isoflurane: (Major) Due to the potential for QT interval prolongation with primaquine, caution is advised with other drugs that prolong the QT interval. Drugs with a possible risk for QT prolongation and TdP that should be used cautiously and with close monitoring with primaquine include halogenated anesthetics.
Itraconazole: (Moderate) Caution is advised during concurrent use of itraconazole and primaquine as both drugs may cause QT prolongation.
Ivosidenib: (Major) Avoid coadministration of ivosidenib with primaquine due to an increased risk of QT prolongation. If concomitant use is unavoidable, monitor ECGs for QTc prolongation and monitor electrolytes; correct any electrolyte abnormalities as clinically appropriate. An interruption of therapy and dose reduction of ivosidenib may be necessary if QT prolongation occurs. Prolongation of the QTc interval and ventricular arrhythmias have been reported in patients treated with ivosidenib. Primaquine may also cause QT interval prolongation.
Ketoconazole: (Contraindicated) Avoid concomitant use of ketoconazole and primaquine due to an increased risk for torsade de pointes (TdP) and QT/QTc prolongation.
Lansoprazole; Amoxicillin; Clarithromycin: (Major) Due to the potential for QT interval prolongation with primaquine, caution is advised with other drugs that prolong the QT interval. Drugs with a possible risk for QT prolongation and TdP that should be used cautiously and with close monitoring with primaquine include clarithromycin.
Lapatinib: (Moderate) Monitor for evidence of QT prolongation if lapatinib is administered with primaquine. Lapatinib has been associated with concentration-dependent QT prolongation; ventricular arrhythmias and torsade de pointes (TdP) have been reported in postmarketing experience with lapatinib. Primaquine also has the potential for QT prolongation.
Lefamulin: (Major) Avoid coadministration of lefamulin with primaquine as concurrent use may increase the risk of QT prolongation. If coadministration cannot be avoided, monitor ECG during treatment. Lefamulin has a concentration dependent QTc prolongation effect. The pharmacodynamic interaction potential to prolong the QT interval of the electrocardiogram between lefamulin and other drugs that effect cardiac conduction is unknown. Primaquine has also been associated with QT interval prolongation.
Lenvatinib: (Major) Avoid coadministration of lenvatinib with primaquine due to the risk of QT prolongation. Prolongation of the QT interval has been reported with lenvatinib therapy. Primaquine also prolongs the QT interval.
Leuprolide: (Moderate) Consider whether the benefits of androgen deprivation therapy (i.e., leuprolide) outweigh the potential risks of QT prolongation in patients receiving primaquine as concurrent use may increase the risk of QT prolongation. Primaquine has the potential to cause QT prolongation. Androgen deprivation therapy may also prolong the QT/QTc interval.
Leuprolide; Norethindrone: (Moderate) Consider whether the benefits of androgen deprivation therapy (i.e., leuprolide) outweigh the potential risks of QT prolongation in patients receiving primaquine as concurrent use may increase the risk of QT prolongation. Primaquine has the potential to cause QT prolongation. Androgen deprivation therapy may also prolong the QT/QTc interval.
Levofloxacin: (Moderate) Concomitant use of levofloxacin and primaquine may increase the risk of QT/QTc prolongation and torsade de pointes (TdP) in some patients. Consider taking steps to minimize the risk of QT/QTc interval prolongation and TdP, such as avoidance, electrolyte monitoring and repletion, and ECG monitoring, especially in patients with additional risk factors for TdP.
Levoketoconazole: (Contraindicated) Avoid concomitant use of ketoconazole and primaquine due to an increased risk for torsade de pointes (TdP) and QT/QTc prolongation.
Lidocaine: (Moderate) Coadministration of lidocaine with oxidizing agents, such as primaquine, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue lidocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Lidocaine; Epinephrine: (Moderate) Coadministration of lidocaine with oxidizing agents, such as primaquine, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue lidocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Lidocaine; Prilocaine: (Moderate) Coadministration of lidocaine with oxidizing agents, such as primaquine, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue lidocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) Coadministration of prilocaine with oxidizing agents, such as primaquine, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue prilocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Lithium: (Moderate) Concomitant use of lithium and primaquine may increase the risk of QT/QTc prolongation and torsade de pointes (TdP) in some patients. Consider taking steps to minimize the risk of QT/QTc interval prolongation and TdP, such as avoidance, electrolyte monitoring and repletion, and ECG monitoring, especially in patients with additional risk factors for TdP.
Lofexidine: (Major) Monitor ECG if lofexidine is coadministered with primaquine due to the potential for additive QT prolongation. Lofexidine prolongs the QT interval. In addition, there are postmarketing reports of torsade de pointes. Primaquine has the potential to prolong the QT interval.
Loperamide: (Moderate) Exercise caution when administering primaquine in combination with loperamide as concurrent use may increase the risk of QT prolongation. Primaquine is associated with QT prolongation. At high doses, loperamide has been associated with serious cardiac toxicities, including syncope, ventricular tachycardia, QT prolongation, torsade de pointes (TdP), and cardiac arrest.
Loperamide; Simethicone: (Moderate) Exercise caution when administering primaquine in combination with loperamide as concurrent use may increase the risk of QT prolongation. Primaquine is associated with QT prolongation. At high doses, loperamide has been associated with serious cardiac toxicities, including syncope, ventricular tachycardia, QT prolongation, torsade de pointes (TdP), and cardiac arrest.
Lopinavir; Ritonavir: (Major) Avoid coadministration of lopinavir with primaquine due to the potential for additive QT prolongation. If use together is necessary, obtain a baseline ECG to assess initial QT interval and determine frequency of subsequent ECG monitoring, avoid any non-essential QT prolonging drugs, and correct electrolyte imbalances. Both drugs are associated with QT prolongation.
Macimorelin: (Major) Avoid concurrent administration of macimorelin with drugs that prolong the QT interval, such as primaquine. Use of these drugs together may increase the risk of developing torsade de pointes-type ventricular tachycardia. Sufficient washout time of drugs that are known to prolong the QT interval prior to administration of macimorelin is recommended. Treatment with macimorelin has been associated with an increase in the corrected QT (QTc) interval. Primaquine has the potential to prolong the QT interval.
Maprotiline: (Moderate) Exercise caution when administering primaquine in combination with maprotiline as concurrent use may increase the risk of QT prolongation. Primaquine is associated with QT prolongation. Maprotiline has been reported to prolong the QT interval, particularly in overdose or with higher-dose prescription therapy (elevated serum concentrations). Cases of long QT syndrome and torsade de pointes (TdP) tachycardia have been described with maprotiline use, but rarely occur when the drug is used alone in normal prescribed doses and in the absence of other known risk factors for QT prolongation. Limited data are available regarding the safety of maprotiline in combination with other QT-prolonging drugs.
Mefloquine: (Moderate) Mefloquine should be used with caution in patients receiving primaquine as concurrent use may increase the risk of QT prolongation. There is evidence that the use of halofantrine after mefloquine causes a significant lengthening of the QTc interval. Mefloquine alone has not been reported to cause QT prolongation. Primaquine is associated with QT prolongation.
Mepivacaine: (Moderate) Coadministration of mepivacaine with oxidizing agents, such as primaquine, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue mepivacaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Methadone: (Major) Due to the potential for QT interval prolongation with primaquine, caution is advised with other drugs that prolong the QT interval. Drugs with a possible risk for QT prolongation and TdP that should be used cautiously and with close monitoring with primaquine include methadone.
Metronidazole: (Moderate) Concomitant use of metronidazole and primaquine may increase the risk of QT/QTc prolongation and torsade de pointes (TdP) in some patients. Consider taking steps to minimize the risk of QT/QTc interval prolongation and TdP, such as avoidance, electrolyte monitoring and repletion, and ECG monitoring, especially in patients with additional risk factors for TdP.
Midostaurin: (Major) The concomitant use of midostaurin and primaquine may lead to additive QT interval prolongation. If these drugs are used together, consider electrocardiogram monitoring. In clinical trials, QT prolongation has been reported in patients who received midostaurin as single-agent therapy or in combination with cytarabine and daunorubicin.
Mifepristone: (Major) Avoid use together if possible; consider alternative therapies to primaquine. Due to the potential for QT interval prolongation with primaquine, caution is advised with other drugs that prolong the QT interval. Drugs with a possible risk for QT prolongation and TdP that should be used cautiously and with close monitoring with primaquine include mifepristone. Mifepristone, when used chronically for hormonal conditions, such as Cushing's syndrome, has been associated with QT prolongation. To limit the risk for QT prolongation, the lowest effective dose of mifepristone should be used. Closely monitor.
Mirtazapine: (Moderate) Concomitant use of mirtazapine and primaquine may increase the risk of QT/QTc prolongation and torsade de pointes (TdP) in some patients. Consider taking steps to minimize the risk of QT/QTc interval prolongation and TdP, such as avoidance, electrolyte monitoring and repletion, and ECG monitoring, especially in patients with additional risk factors for TdP.
Mobocertinib: (Major) Concomitant use of mobocertinib and primaquine increases the risk of QT/QTc prolongation and torsade de pointes (TdP). Avoid concomitant use if possible, especially in patients with additional risk factors for TdP. Consider taking steps to minimize the risk for QT/QTc interval prolongation and TdP, such as electrolyte monitoring and repletion and ECG monitoring, if concomitant use is necessary.
Moxifloxacin: (Major) Due to the potential for QT interval prolongation with primaquine, caution is advised with other drugs that prolong the QT interval. Drugs with a possible risk for QT prolongation and TdP that should be used cautiously and with close monitoring with primaquine include moxifloxacin.
Nilotinib: (Major) Avoid the concomitant use of nilotinib and primaquine; significant prolongation of the QT interval may occur. Sudden death and QT prolongation have been reported in patients who received nilotinib therapy. Primaquine has the potential to prolong the QT interval.
Ofloxacin: (Moderate) Concomitant use of ofloxacin and primaquine may increase the risk of QT/QTc prolongation and torsade de pointes (TdP) in some patients. Consider taking steps to minimize the risk of QT/QTc interval prolongation and TdP, such as avoidance, electrolyte monitoring and repletion, and ECG monitoring, especially in patients with additional risk factors for TdP.
Olanzapine: (Moderate) Exercise caution when administering primaquine in combination with olanzapine as concurrent use may increase the risk of QT prolongation. Primaquine is associated with QT prolongation. Limited data, including some case reports, suggest that olanzapine may be associated with a significant prolongation of the QTc interval.
Olanzapine; Fluoxetine: (Moderate) Concomitant use of fluoxetine and primaquine may increase the risk of QT/QTc prolongation and torsade de pointes (TdP) in some patients. Consider taking steps to minimize the risk of QT/QTc interval prolongation and TdP, such as avoidance, electrolyte monitoring and repletion, and ECG monitoring, especially in patients with additional risk factors for TdP. (Moderate) Exercise caution when administering primaquine in combination with olanzapine as concurrent use may increase the risk of QT prolongation. Primaquine is associated with QT prolongation. Limited data, including some case reports, suggest that olanzapine may be associated with a significant prolongation of the QTc interval.
Olanzapine; Samidorphan: (Moderate) Exercise caution when administering primaquine in combination with olanzapine as concurrent use may increase the risk of QT prolongation. Primaquine is associated with QT prolongation. Limited data, including some case reports, suggest that olanzapine may be associated with a significant prolongation of the QTc interval.
Ondansetron: (Major) Concomitant use of primaquine and ondansetron increases the risk of QT/QTc prolongation and torsade de pointes (TdP). Avoid concomitant use if possible, especially in patients with additional risk factors for TdP. Consider taking steps to minimize the risk for QT/QTc interval prolongation and TdP, such as electrolyte monitoring and repletion and ECG monitoring, if concomitant use is necessary. Do not exceed 16 mg of IV ondansetron in a single dose; the degree of QT prolongation associated with ondansetron significantly increases above this dose.
Osilodrostat: (Moderate) Monitor ECGs in patients receiving osilodrostat with primaquine as concurrent use may increase the risk of QT prolongation. Osilodrostat is associated with dose-dependent QT prolongation. Primaquine has the potential to prolong the QT interval.
Osimertinib: (Major) Avoid coadministration of primaquine with osimertinib if possible due to the risk of QT prolongation and torsade de pointes (TdP). If concomitant use is unavoidable, periodically monitor ECGs for QT prolongation and monitor electrolytes; an interruption of osimertinib therapy with dose reduction or discontinuation of therapy may be necessary if QT prolongation occurs. Concentration-dependent QTc prolongation occurred during clinical trials of osimertinib. Primaquine may also cause QT interval prolongation.
Oxaliplatin: (Major) Monitor electrolytes and ECGs for QT prolongation if coadministration of primaquine with oxaliplatin is necessary; correct electrolyte abnormalities prior to administration of oxaliplatin. Primaquine has been associated with QT prolongation; QT prolongation and ventricular arrhythmias including fatal torsade de pointes have also been reported with oxaliplatin use in postmarketing experience.
Ozanimod: (Major) In general, do not initiate ozanimod in patients taking primaquine due to the risk of additive bradycardia, QT prolongation, and torsade de pointes (TdP). If treatment initiation is considered, seek advice from a cardiologist. Ozanimod initiation may result in a transient decrease in heart rate and atrioventricular conduction delays. Ozanimod has not been studied in patients taking concurrent QT prolonging drugs; however, QT prolonging drugs have been associated with TdP in patients with bradycardia. Primaquine has been associated with QT interval prolongation.
Pacritinib: (Major) Concomitant use of pacritinib and primaquine increases the risk of QT/QTc prolongation and torsade de pointes (TdP). Avoid concomitant use if possible, especially in patients with additional risk factors for TdP. Consider taking steps to minimize the risk for QT/QTc interval prolongation and TdP, such as electrolyte monitoring and repletion and ECG monitoring, if concomitant use is necessary.
Paliperidone: (Major) Paliperidone has been associated with QT prolongation; torsade de pointes (TdP) and ventricular fibrillation have been reported in the setting of overdose. According to the manufacturer, since paliperidone may prolong the QT interval, it should be avoided in combination with other agents also known to have this effect, including primaquine. If coadministration is necessary and the patient has known risk factors for cardiac disease or arrhythmias, close monitoring is essential.
Pasireotide: (Moderate) Use caution when using pasireotide in combination with primaquine as concurrent use may increase the risk of QT prolongation. QT prolongation has occurred with pasireotide at therapeutic and supra-therapeutic doses. Primaquine is associated with QT prolongation.
Pazopanib: (Major) Due to the potential for QT interval prolongation with primaquine, caution is advised with other drugs that prolong the QT interval. Drugs with a possible risk for QT prolongation and TdP that should be used cautiously and with close monitoring with primaquine include pazopanib.
Penicillamine: (Major) Do not use penicillamine concurrently with antimalarials due to an increased risk of severe hematologic and renal adverse reactions.
Penicillin G Benzathine; Penicillin G Procaine: (Moderate) Coadministration of penicillin G procaine with oxidizing agents, such as primaquine, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue penicillin G procaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Penicillin G Procaine: (Moderate) Coadministration of penicillin G procaine with oxidizing agents, such as primaquine, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue penicillin G procaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Pentamidine: (Major) Due to the potential for QT interval prolongation with primaquine, caution is advised with other drugs that prolong the QT interval. Drugs with a possible risk for QT prolongation and TdP that should be used cautiously and with close monitoring with primaquine include pentamidine.
Perphenazine: (Minor) Exercise caution when administering primaquine in combination with perphenazine as concurrent use may increase the risk of QT prolongation. Primaquine is associated with QT prolongation. Perphenazine is associated with a possible risk for QT prolongation. Theoretically, this phenothiazine may increase the risk of QT prolongation if coadministered with drugs with a risk of QT prolongation.
Perphenazine; Amitriptyline: (Minor) Exercise caution when administering primaquine in combination with perphenazine as concurrent use may increase the risk of QT prolongation. Primaquine is associated with QT prolongation. Perphenazine is associated with a possible risk for QT prolongation. Theoretically, this phenothiazine may increase the risk of QT prolongation if coadministered with drugs with a risk of QT prolongation.
Pimavanserin: (Major) Pimavanserin may cause QT prolongation and should generally be avoided in patients receiving other medications known to prolong the QT interval, such as primaquine. Coadministration may increase the risk for QT prolongation.
Pimozide: (Contraindicated) Primaquine has the potential to prolong the QT interval. Pimozide is associated with a well-established risk of QT prolongation and torsade de pointes (TdP). Because of the potential for TdP, use of primaquine with pimozide is contraindicated.
Pitolisant: (Major) Avoid coadministration of pitolisant with primaquine as concurrent use may increase the risk of QT prolongation. Pitolisant prolongs the QT interval. Primaquine has also been associated with QT interval prolongation.
Ponesimod: (Major) In general, do not initiate ponesimod in patients taking primaquine due to the risk of additive bradycardia, QT prolongation, and torsade de pointes (TdP). If treatment initiation is considered, seek advice from a cardiologist. Ponesimod initiation may result in a transient decrease in heart rate and atrioventricular conduction delays. Ponesimod has not been studied in patients taking concurrent QT prolonging drugs; however, QT prolonging drugs have been associated with TdP in patients with bradycardia. Primaquine has been associated with QT interval prolongation.
Posaconazole: (Moderate) Use posaconazole with caution in combination with primaquine as concurrent use may increase the risk of QT prolongation. Posaconazole has been associated with prolongation of the QT interval as well as rare cases of torsade de pointes. Primaquine also has the potential to prolong the QT interval.
Prilocaine: (Moderate) Coadministration of prilocaine with oxidizing agents, such as primaquine, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue prilocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Prilocaine; Epinephrine: (Moderate) Coadministration of prilocaine with oxidizing agents, such as primaquine, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue prilocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Procainamide: (Major) Due to the potential for QT interval prolongation with primaquine, caution is advised with other drugs that prolong the QT interval. Drugs with a possible risk for QT prolongation and TdP that should be used cautiously and with close monitoring with primaquine include procainamide.
Prochlorperazine: (Minor) Exercise caution when administering primaquine in combination with primaquine as concurrent use may increase the risk of QT prolongation. Primaquine is associated with QT prolongation. Prochlorperazine is associated with a possible risk for QT prolongation. Theoretically, prochlorperazine may increase the risk of QT prolongation if coadministered with primaquine.
Promethazine: (Moderate) Concomitant use of promethazine and primaquine may increase the risk of QT/QTc prolongation and torsade de pointes (TdP) in some patients. Consider taking steps to minimize the risk of QT/QTc interval prolongation and TdP, such as avoidance, electrolyte monitoring and repletion, and ECG monitoring, especially in patients with additional risk factors for TdP.
Promethazine; Dextromethorphan: (Moderate) Concomitant use of promethazine and primaquine may increase the risk of QT/QTc prolongation and torsade de pointes (TdP) in some patients. Consider taking steps to minimize the risk of QT/QTc interval prolongation and TdP, such as avoidance, electrolyte monitoring and repletion, and ECG monitoring, especially in patients with additional risk factors for TdP.
Promethazine; Phenylephrine: (Moderate) Concomitant use of promethazine and primaquine may increase the risk of QT/QTc prolongation and torsade de pointes (TdP) in some patients. Consider taking steps to minimize the risk of QT/QTc interval prolongation and TdP, such as avoidance, electrolyte monitoring and repletion, and ECG monitoring, especially in patients with additional risk factors for TdP.
Propafenone: (Major) Concomitant use of propafenone and primaquine increases the risk of QT/QTc prolongation and torsade de pointes (TdP). Avoid concomitant use if possible, especially in patients with additional risk factors for TdP. Consider taking steps to minimize the risk for QT/QTc interval prolongation and TdP, such as electrolyte monitoring and repletion and ECG monitoring, if concomitant use is necessary.
Quetiapine: (Major) Concomitant use of quetiapine and primaquine increases the risk of QT/QTc prolongation and torsade de pointes (TdP). Avoid concomitant use if possible, especially in patients with additional risk factors for TdP. Consider taking steps to minimize the risk for QT/QTc interval prolongation and TdP, such as electrolyte monitoring and repletion and ECG monitoring, if concomitant use is necessary.
Quinidine: (Major) Due to the potential for QT interval prolongation with primaquine, caution is advised with other drugs that prolong the QT interval. Drugs with a possible risk for QT prolongation and TdP that should be used cautiously and with close monitoring with primaquine include quinidine.
Quinine: (Major) Due to the potential for QT interval prolongation with primaquine, caution is advised with other drugs that prolong the QT interval. Drugs with a possible risk for QT prolongation and TdP that should be used cautiously and with close monitoring with primaquine include quinine.
Quizartinib: (Major) Concomitant use o

f quizartinib and primaquine increases the risk of QT/QTc prolongation and torsade de pointes (TdP). Avoid concomitant use if possible, especially in patients with additional risk factors for TdP. Consider taking steps to minimize the risk for QT/QTc interval prolongation and TdP, such as electrolyte monitoring and repletion and ECG monitoring, if concomitant use is necessary.
Rabies Vaccine: (Major) If administered concurrently, antimalarials can impair the immunologic response to the rabies vaccine, thereby, decreasing its protective effect. If possible, administration of antimalarials should be avoided during use of the rabies vaccine for postexposure prophylaxis. When antimalarials must be administered to persons also receiving the rabies vaccine for postexposure prophylaxis, a serum rabies antibody titer should be obtained on day 14 (day of the 4th vaccination) to ensure an acceptable antibody response has been induced.
Ranolazine: (Moderate) Exercise caution when administering primaquine in combination with ranolazine. Primaquine is associated with QT prolongation. Ranolazine is associated with dose- and plasma concentration-related increases in the QTc interval. Although there are no studies examining the effects of ranolazine in patients receiving other QT prolonging drugs, coadministration of such drugs may result in additive QT prolongation.
Relugolix: (Moderate) Due to the potential for QT interval prolongation with primaquine, caution is advised with other drugs that prolong the QT interval. Androgen deprivation therapy (i.e., relugolix) may also prolong the QT/QTc interval.
Relugolix; Estradiol; Norethindrone acetate: (Moderate) Due to the potential for QT interval prolongation with primaquine, caution is advised with other drugs that prolong the QT interval. Androgen deprivation therapy (i.e., relugolix) may also prolong the QT/QTc interval.
Ribociclib: (Major) Avoid coadministration of ribociclib with primaquine due to an increased risk for QT prolongation. Ribociclib has been shown to prolong the QT interval in a concentration-dependent manner. Primaquine has also been associated with QT prolongation. Concomitant use may increase the risk for QT prolongation.
Ribociclib; Letrozole: (Major) Avoid coadministration of ribociclib with primaquine due to an increased risk for QT prolongation. Ribociclib has been shown to prolong the QT interval in a concentration-dependent manner. Primaquine has also been associated with QT prolongation. Concomitant use may increase the risk for QT prolongation.
Rilpivirine: (Moderate) Exercise caution when administering primaquine in combination with rilpivirine as concurrent use may increase the risk of QT prolongation. Primaquine is associated with QT prolongation. Supratherapeutic doses of rilpivirine (75 to 300 mg/day) have caused QT prolongation.
Risperidone: (Moderate) Use risperidone and primaquine together with caution due to the potential for additive QT prolongation and risk of torsade de pointes (TdP). Risperidone has been associated with a possible risk for QT prolongation and/or TdP, primarily in the overdose setting. Primaquine has also been associated with QT prolongation.
Romidepsin: (Moderate) Consider monitoring electrolytes and ECGs at baseline and periodically during treatment if romidepsin is administered with primaquine as concurrent use may increase the risk of QT prolongation. Romidepsin has been reported to prolong the QT interval. Primaquine is associated with QT prolongation.
Ropivacaine: (Moderate) Coadministration of ropivacaine with oxidizing agents, such as primaquine, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue ropivacaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Saquinavir: (Major) Due to the potential for QT interval prolongation with primaquine, caution is advised with other drugs that prolong the QT interval. Drugs with a possible risk for QT prolongation and TdP that should be used cautiously and with close monitoring with primaquine include saquinavir.
Selpercatinib: (Major) Monitor ECGs more frequently for QT prolongation if coadministration of selpercatinib with primaquine is necessary due to the risk of additive QT prolongation. Concentration-dependent QT prolongation has been observed with selpercatinib therapy. Primaquine has been associated with QT interval prolongation.
Sertraline: (Moderate) Concomitant use of sertraline and primaquine may increase the risk of QT/QTc prolongation and torsade de pointes (TdP) in some patients. Consider taking steps to minimize the risk of QT/QTc interval prolongation and TdP, such as avoidance, electrolyte monitoring and repletion, and ECG monitoring, especially in patients with additional risk factors for TdP. The degree of QT prolongation associated with sertraline is not clinically significant when administered within the recommended dosage range; QT prolongation has been described at 2 times the maximum recommended dose.
Sevoflurane: (Major) Due to the potential for QT interval prolongation with primaquine, caution is advised with other drugs that prolong the QT interval. Drugs with a possible risk for QT prolongation and TdP that should be used cautiously and with close monitoring with primaquine include halogenated anesthetics.
Siponimod: (Major) In general, do not initiate treatment with siponimod in patients receiving primaquine due to the potential for QT prolongation. Consult a cardiologist regarding appropriate monitoring if siponimod use is required. Siponimod therapy prolonged the QT interval at recommended doses in a clinical study. Primaquine has the potential to prolong the QT interval.
Sodium Stibogluconate: (Moderate) Concomitant use of sodium stibogluconate and primaquine may increase the risk of QT/QTc prolongation and torsade de pointes (TdP) in some patients. Consider taking steps to minimize the risk of QT/QTc interval prolongation and TdP, such as avoidance, electrolyte monitoring and repletion, and ECG monitoring, especially in patients with additional risk factors for TdP.
Solifenacin: (Moderate) Exercise caution when administering primaquine in combination with solifenacin as concurrent use may increase the risk of QT prolongation. Primaquine is associated with QT prolongation. Solifenacin has been associated with dose-dependent prolongation of the QT interval. Torsade de pointes (TdP) has been reported with postmarketing use, although causality was not determined. This should be taken into consideration when prescribing solifenacin to patients taking primaquine.
Sorafenib: (Major) Avoid coadministration of sorafenib with primaquine due to the risk of additive QT prolongation. If concomitant use is unavoidable, monitor electrocardiograms and correct electrolyte abnormalities. An interruption or discontinuation of sorafenib therapy may be necessary if QT prolongation occurs. Both drugs are associated with QTc prolongation.
Sotalol: (Major) Concomitant use of sotalol and primaquine increases the risk of QT/QTc prolongation and torsade de pointes (TdP). Avoid concomitant use if possible, especially in patients with additional risk factors for TdP. Consider taking steps to minimize the risk for QT/QTc interval prolongation and TdP, such as electrolyte monitoring and repletion and ECG monitoring, if concomitant use is necessary.
Sunitinib: (Moderate) Monitor for evidence of QT prolongation if sunitinib is administered with primaquine. Primaquine has the potential for QT interval prolongation. Sunitinib can prolong the QT interval.
Tacrolimus: (Moderate) Consider ECG and electrolyte monitoring periodically during treatment if tacrolimus is administered with primaquine. Tacrolimus may prolong the QT interval and cause torsade de pointes (TdP). Primaquine is associated with QT prolongation.
Tamoxifen: (Moderate) Concomitant use of tamoxifen and primaquine may increase the risk of QT/QTc prolongation and torsade de pointes (TdP) in some patients. Consider taking steps to minimize the risk of QT/QTc interval prolongation and TdP, such as avoidance, electrolyte monitoring and repletion, and ECG monitoring, especially in patients with additional risk factors for TdP.
Telavancin: (Moderate) Exercise caution when administering primaquine in combination with telavancin as concurrent use may increase the risk of QT prolongation. Primaquine is associated with QT prolongation. Telavancin has been associated with QT prolongation.
Tetrabenazine: (Major) Due to the potential for QT interval prolongation with primaquine, caution is advised with other drugs that prolong the QT interval. Drugs with a possible risk for QT prolongation and TdP that should be used cautiously and with close monitoring with primaquine include tetrabenazine.
Tetracaine: (Moderate) Coadministration of tetracaine with oxidizing agents, such as primaquine, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue tetracaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Thioridazine: (Contraindicated) Primaquine has the potential to prolong the QT interval. Thioridazine is associated with a well-established risk of QT prolongation and torsades de pointes (TdP). Thioridazine is considered contraindicated for use along with agents that, when combined with a phenothiazine, may prolong the QT interval and increase the risk of TdP, and/or cause orthostatic hypotension. Because of the potential for TdP, use of primaquine with thioridazine is contraindicated.
Tolterodine: (Moderate) Exercise caution when administering primaquine in combination with tolterodine as concurrent use may increase the risk of QT prolongation. Primaquine is associated with QT prolongation. Tolterodine has been associated with dose-dependent prolongation of the QT interval, especially in poor CYP2D6 metabolizers.
Toremifene: (Major) Avoid coadministration of primaquine with toremifene if possible due to the risk of additive QT prolongation. If concomitant use is unavoidable, closely monitor ECGs for QT prolongation and monitor electrolytes; correct hypokalemia or hypomagnesemia prior to administration of toremifene. Toremifene has been shown to prolong the QTc interval in a dose- and concentration-related manner. Primaquine may also cause QT prolongation.
Trazodone: (Major) Concomitant use of trazodone and primaquine increases the risk of QT/QTc prolongation and torsade de pointes (TdP). Avoid concomitant use if possible, especially in patients with additional risk factors for TdP. Consider taking steps to minimize the risk for QT/QTc interval prolongation and TdP, such as electrolyte monitoring and repletion and ECG monitoring, if concomitant use is necessary.
Triclabendazole: (Moderate) Concomitant use of triclabendazole and primaquine may increase the risk of QT/QTc prolongation and torsade de pointes (TdP) in some patients. Consider taking steps to minimize the risk of QT/QTc interval prolongation and TdP, such as avoidance, electrolyte monitoring and repletion, and ECG monitoring, especially in patients with additional risk factors for TdP.
Trifluoperazine: (Minor) Trifluoperazine is associated with a possible risk for QT prolongation. Theoretically, this phenothiazine may increase the risk of QT prolongation if coadministered with drugs with a risk of QT prolongation, such as primaquine. Administer these agents and drugs that can prolong the QT interval with caution.
Triptorelin: (Moderate) Consider whether the benefits of androgen deprivation therapy (i.e., triptorelin) outweigh the potential risks of QT prolongation in patients receiving primaquine as concurrent use may increase the risk of QT prolongation. Primaquine has the potential to cause QT prolongation. Androgen deprivation therapy may also prolong the QT/QTc interval.
Vandetanib: (Major) Avoid coadministration of vandetanib with primaquine due to an increased risk of QT prolongation and torsade de pointes (TdP). If concomitant use is unavoidable, monitor ECGs for QT prolongation and monitor electrolytes; correct hypocalcemia, hypomagnesemia, and/or hypomagnesemia prior to vandetanib administration. An interruption of vandetanib therapy or dose reduction may be necessary for QT prolongation. Vandetanib can prolong the QT interval in a concentration-dependent manner; TdP and sudden death have been reported in patients receiving vandetanib. Primaquine also has the potential to cause QT prolongation.
Vardenafil: (Moderate) Concomitant use of vardenafil and primaquine may increase the risk of QT/QTc prolongation and torsade de pointes (TdP) in some patients. Consider taking steps to minimize the risk of QT/QTc interval prolongation and TdP, such as avoidance, electrolyte monitoring and repletion, and ECG monitoring, especially in patients with additional risk factors for TdP.
Vemurafenib: (Major) Due to the potential for QT interval prolongation with primaquine, caution is advised with other drugs that prolong the QT interval. Drugs with a possible risk for QT prolongation and TdP that should be used cautiously and with close monitoring with primaquine include vemurafenib.
Venlafaxine: (Moderate) Concomitant use of venlafaxine and primaquine may increase the risk of QT/QTc prolongation and torsade de pointes (TdP) in some patients. Consider taking steps to minimize the risk of QT/QTc interval prolongation and TdP, such as avoidance, electrolyte monitoring and repletion, and ECG monitoring, especially in patients with additional risk factors for TdP.
Voclosporin: (Moderate) Concomitant use of voclosporin and primaquine may increase the risk of QT prolongation. Consider interventions to minimize the risk of progression to torsades de pointes (TdP), such as ECG monitoring and correcting electrolyte abnormalities, particularly in patients with additional risk factors for TdP. Voclosporin has been associated with QT prolongation at supratherapeutic doses. Primaquine is also associated with QT interval prolongation.
Vonoprazan; Amoxicillin; Clarithromycin: (Major) Due to the potential for QT interval prolongation with primaquine, caution is advised with other drugs that prolong the QT interval. Drugs with a possible risk for QT prolongation and TdP that should be used cautiously and with close monitoring with primaquine include clarithromycin.
Voriconazole: (Moderate) Exercise caution when administering primaquine in combination with voriconazole as concurrent use may increase the risk of QT prolongation. Primaquine is associated with QT prolongation. Voriconazole has been associated with QT prolongation and rare cases of torsade de pointes.
Vorinostat: (Moderate) Exercise caution when administering primaquine in combination with vorinostat. Primaquine and vorinostat are associated with QT prolongation.
Ziprasidone: (Major) Concomitant use of ziprasidone and primaquine should be avoided due to the potential for additive QT prolongation. Clinical trial data indicate that ziprasidone causes QT prolongation; there are postmarketing reports of torsade de pointes (TdP) in patients with multiple confounding factors. Primaquine has the potential for QT prolongation.

Primaquine/Primaquine Phosphate Oral Tab: 26.3mg

Adults

15 mg base PO daily is FDA-approved; however, doses of 30 mg base PO daily are recommended off-label.

Geriatric

15 mg base PO daily is FDA-approved; however, doses of 30 mg base PO daily are recommended off-label.

Adolescents

Safety and efficacy have not been established; however, doses up to 0.5 mg/kg/day base PO (Max: 30 mg base) have been used off-label.

Children

Safety and efficacy have not been established; however, doses up to 0.5 mg/kg/day base PO (Max: 30 mg base) have been used off-label.

Infants

Safety and efficacy have not been established; however, doses up to 0.5 mg/kg/day base PO have been used off-label.

Neonates

Safety and efficacy have not been established.

Mechanism of Action: Primaquine's exact mechanism of action has not been fully elucidated. Unlike other antimalarials, primaquine is a tissue schizonticidal agent used in the treatment of malaria caused by P. vivax and P. ovale and is also effective against gametocytes of P. falciparum. Primaquine is effective against the preerythrocytic and exoerythrocytic forms of P. falciparum, P. malariae, P. oval, and P. vivax. It is believed that action stems from the drug's ability to interfere with the function of plasmodial DNA. Activity of primaquine against gametocytes of P. falciparum disrupts transmission of the disease.

Primaquine is administered orally. Following absorption, the drug is almost undetectable after 24 hours. There does appear to be considerable individual patient variation in drug response.
 
Primaquine is widely distributed throughout the body, and unlike chloroquine or hydroxychloroquine, there is no accumulation in erythrocytes. Rapid metabolism of the drug occurs to produce three identifiable metabolites. The major metabolite is carboxyprimaquine, which greatly exceeds plasma concentrations of the parent drug. Carboxyprimaquine is eliminated more slowly than primaquine and accumulates with multiple dosing. The amount of carboxyprimaquine's antimalarial activity is unknown. The other metabolites possess hemolytic activity in vitro. Plasma half-life for primaquine is about 6 hours and for carboxyprimaquine 22—30 hours. An extremely small amount of primaquine is excreted in the urine.

Oral Route

Following oral administration, primaquine is rapidly absorbed from the GI tract. Oral bioavailability is roughly 96%, with peak plasma levels achieved in about 3 hours.

Pregnancy

Primaquine is contraindicated in pregnancy. Even if a pregnant woman is glucose-6-phosphate dehydrogenase (G6PD) normal, the fetus may not be G6PD normal. Primaquine crosses the placenta, and the fetus could develop hemolytic anemia if G6PD-deficient.

Primaquine may be associated with reproductive risk. Complete pregnancy testing for sexually-active females of reproductive potential prior to use. Discuss contraception requirements with the patient. Advise sexually-active females of child bearing potential to use effective contraception during primaquine use and after stopping therapy until the completion of an ongoing ovulatory cycle (e.g., up to the next menses). Due to the potential of male-mediated teratogenicity, advise males with partners that may become pregnant to use a condom while on treatment and for 3 months after stopping treatment with primaquine. Nonclinical data from studies conducted in bacteria and animals treated with primaquine show evidence of gene mutations and chromosomal/DNA damage, teratogenicity, and injury to embryos and developing fetuses.