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    Antiinfectives and Antiseptics for Local Oral Treatment
    Antiseptics and Disinfectants, Excluding Hand Products

    DEA CLASS

    OTC, Rx

    DESCRIPTION

    Topical antimicrobial agent
    Bacterial spectrum includes both gram-positive and gram-negative organisms, some viruses including HIV, and fungi; sporicidal only at elevated temperatures
    Used as an oral rinse, topical skin cleanser, and is incorporated into several types of medical devices

    COMMON BRAND NAMES

    Betasept, Hibiclens, Oro Clense, Peridex, Periogard, PerioRx, Perisol

    HOW SUPPLIED

    Betasept/Chlorhexidine/Chlorhexidine Gluconate/Hibiclens Topical Sol: 4%
    Chlorhexidine/Chlorhexidine Gluconate/Oro Clense/Peridex/Periogard/PerioRx/Perisol Oral Sol: 0.12%
    Chlorhexidine/Chlorhexidine Gluconate/Oro Clense/Peridex/Periogard/PerioRx/Perisol Periodontal Sol: 0.12%
    Peridex Buccal Liq: 0.12%

    DOSAGE & INDICATIONS

    For the treatment of gingivitis.
    Oral Rinse dosage
    Adults

    Rinse mouth with 15 mL of chlorhexidine oral rinse for 30 seconds twice daily following toothbrushing. Do not swallow or dilute. Expectorate after rinsing. Therapy with chlorhexidine oral rinse should begin immediately following dental prophylaxis. Reevaluate and continue dental prophylaxis at least every 6 months. The rinse has not been tested among patients with acute necrotizing ulcerative gingivitis (ANUG).

    For the adjuvant treatment and maintenance of adult periodontitis.
    Periodontal insert dosage (PerioChip peridontal insert)
    Adults

    Insert 1 chlorhexidine periodontal insert (PerioChip 2.5 mg) into a periodontal pocket with a probing pocket depth of 5 mm or more. Up to 8 periodontal inserts may be inserted in a single visit. Treatment is recommended every 3 months in pockets with a depth of 5 mm or more. This treatment is in addition to scaling and root planing for the reduction of pocket depth in adult patients with periodontitis. Chlorhexidine dental implants may be used as part of a periodontal maintenance program which, would also include good oral hygiene, scaling and root planing.

    For use as skin antisepsis.
    Topical dosage (surgical hand scrub)
    Adults

    Wet hands and forearms with warm water. Apply approximately 5 mL and scrub for 3 minutes using a wet sponge or brush. Wash for an additional 3 minutes with 5 mL and rinse under running water. Dry thoroughly.

    Topical dosage (sponge/brush for surgical hand scrub)
    Adults

    Wet hands. Use nail cleaner under fingernails and to clean cuticles. Wet hands and forearms to elbow. Wet sponge side of sponge/brush. Squeeze and pump sponge immediately to work up adequate lather. Apply lather to hands and forearms using sponge side. Start 3 minute scrub by using the brush side to scrub only the nails, cuticles, and interdigital areas. Use sponge side for scrubbing hands and forearms (avoid using brush on more sensitive areas). Rinse thoroughly with warm water. Scrub for an additional 3 minutes using sponge side only. To produce additional lather, add a small amount of water and pump sponge. While scrubbing, do not use excessive pressure to produce lather; only a small amount of lather is required to adequately clean skin. Rinse and dry thoroughly using a sterile towel.

    Topical dosage (lotion pump for surgical hand scrub)
    Adults

    Dispense 1 pump (2 mL) into the palm of 1 clean, dry hand. Dip the fingertips of the opposite hand into the lotion and work it under the nails. Spread the remaining lotion over then hand and up to just above the elbow. Use another 2 mL of lotion to repeat the process with the other hand. Dispense another 2 mL of lotion into either hand; reapply to all aspects of both hands up to the wrists.

    Topical dosage (healthcare personnel handwash)
    Adults

    Use approximately 5 mL into cupped hand and wash in a vigorous manner for 15 seconds. Rinse and dry thoroughly.

    Topical dosage (lotion pump for healthcare personnel handwash)
    Adults

    Dispense 1 pump (2 mL) into the palm of 1 clean, dry hand. Paying particular attention to the spaces between the fingers and under fingernails, apply the lotion evenly to cover both hands up to the wrists. Allow to dry without wiping.

    Topical dosage (preoperative skin preparation)
    Adults, Adolescents, Children, Infants, and Neonates

    Apply liberally to surgical site and swab for at least 2 minutes. Dry with sterile towel. Repeat for an additional 2 minutes. NOTE: Use with caution in infants less than 2 months of age: use may cause irritation or chemical burns.

    Topical dosage (applicator for preoperative skin preparation)
    Adults, Adolescents, Children, Infants, and Neonates

    Using applicator, apply solution to completely wet the treatment area. For dry surgical sites (e.g., abdomen or arm) apply solution using repeated back-and-forth strokes for 30 seconds. For moist surgical sites (e.g., inguinal fold) apply solution using repeated back-and-forth strokes for 2 minutes. Do not allow solution to pool; remove excess solution using tuck prep towels. NOTE: Use with caution in infants less than 2 months of age: use may cause irritation or chemical burns.

    Topical Antisepsis Use (swabstick)
    Adults, Adolescents, Children, Infants, and Neonates

    Peel apart the pouch to expose swabstick and remove from package without touching the foam tip. Apply the swabstick to the procedure site prior to surgery or injection. Place 1 flat side of the foam tip on the proposed skin site and prep the skin in vigorous back-and-forth strokes for 1 minute then repeat with the other (unused) side of the swabstick. Allow the area to air dry for 1 minute and 30 seconds (1.5 minutes). Do not blot or wipe dry. Discard after 1 use. NOTE: Use with caution in infants less than 2 months of age: use may cause irritation or chemical burns.

    Topical dosage (skin wound and general skin cleansing)
    Adults, Adolescents, Children, Infants, and Neonates

    Thoroughly rinse the area to be cleaned with water. Apply the minimum amount of product necessary to cover the skin or wound area and wash gently. Rinse again thoroughly. NOTE: Use with caution in infants less than 2 months of age: use may cause irritation or chemical burns.

    For the amelioration of oral stomatitis† and mucositis† associated with cytoreductive chemotherapy in patients preparing for bone marrow transplantation.
    NOTE: This drug is designated as an orphan drug for this indication by the FDA.
    Oral Rinse dosage
    Adults

    The usual dosage is typically used for this off-label indication. Rinse mouth with 15 mL of chlorhexidine oral rinse for 30 seconds twice daily following toothbrushing. Do not swallow or dilute. Expectorate after rinsing.

    For the treatment of denture stomatitis†.
    Denture Soak and Oral Rinse dosage
    Adults

    A standard treatment regimen has not been established. Soaking dentures in chlorhexidine oral rinse for 30 minutes daily has been suggested. In addition, rinsing of the mouth with 15 mL twice daily for 30 seconds (then expectorating) or brushing the gums or dentures twice daily with chlorhexidine oral rinse may be needed to remove denture biofilm. Do not dilute or swallow.

    For use as a skin cleanser in the treatment of acne vulgaris†.
    Topical dosage
    Adults and Adolescents

    Not commonly used; gentle skin cleansers are usually preferred. Wet face. Gently wash affected areas of the face with approximately 5 mL chlorhexidine gluconate 4% skin cleanser (Hibiclens) twice daily, in the morning and evening before going to bed. Rinse face thoroughly. Avoid the eye area. Discontinue use if skin becomes overly dry or if skin irritation occurs.

    †Indicates off-label use

    MAXIMUM DOSAGE

    Adults

    Maximum dosage information not available.

    Geriatric

    Maximum dosage information not available.

    Adolescents

    Maximum dosage information not available.

    Children

    Maximum dosage information not available.

    Infants

    Maximum dosage information not available.

    Neonates

    Maximum dosage information not available.

    DOSING CONSIDERATIONS

    Hepatic Impairment

    Chlorhexidine is poorly absorbed from the GI tract following inadvertent ingestion; excretion is primarily through the feces. Therefore, no dosage adjustments are necessary.

    Renal Impairment

    Chlorhexidine is poorly absorbed from the GI tract following inadvertent ingestion; excretion is primarily through the feces with < 1% excreted in urine. Therefore, no dosage adjustments are necessary.

    ADMINISTRATION

    Topical Administration

    For external use only. Keep out of eyes, ears, and mouth; if accidental exposure occurs, rinse promptly and thoroughly with water. Serious and permanent eye injury has occurred during surgery when chlorhexidine enters and remains in the eye.
    Do not heat solution.
    Apply solution in a well ventilated area to clean, completely dry, residue-free, intact skin.
    Avoid getting the solution into areas with excess hair as the solution may take longer to dry or may not dry completely. When necessary, remove hair using surgical clippers on the morning of surgery. If a wet shave is used, thoroughly remove all soap residues.
    When applying to skin folds, toes, or fingers, use a sterile-gloved hand to hold skin apart until completely dry. Otherwise, skin may adhere to itself.
    To reduce the risk of fire, wait to drape or use ignition sources (e.g., cautery, laser) until solution is completely dry (minimum of 3 minutes on hairless skin; up to 1 hour in hair).
    Tinted solution will slowly fade from skin over time. After the procedure, alcohol may be used to remove tint if desired.
     
    SoluPrep film-foaming sterile surgical solution:
    10.5 mL applicator indicated for use on head, neck, and small prep areas of no more than 13 inches by 13 inches per 1 applicator.
    Hold applicator around the label with thumb on the lever. Do not touch sponge.
    With sponge face parallel to the floor, snap lever. Allow all fluid to flow into sponge.
    26 mL applicator indicated for prep of larger areas below the neck of no more than 19.5 inches by 19.5 inches per 1 applicator.
    Hold applicator with sponge face parallel to the floor. Do not touch sponge.
    Press the end of the applicator. Solution will begin to flow into the sponge.
    Wait for fluid level to reach indicator line of application barrel.
    Completely wet the treatment area. Do not allow solution to pool; use tuck prep towels to absorb and remove excess solution. Do not blot, as this may remove solution from skin.
    Dry surgical sites (e.g., abdomen or arm): Apply using repeated back-and-forth strokes for 30 seconds.
    Moist surgical sites (e.g., inguinal fold): Apply using repeated back-and-forth strokes for 2 minutes.
    Applicators are single use only. After use, discard applicator and any remaining product.
     
    ChloraPrep:
    ChloraPrep One-Step Sepp applicator: Maximum treatment area of no more than 2.5 inches by 2.5 inches per 1 applicator.
    ChloraPrep with Tint applicator: Maximum treatment area of no more than 4 inches by 5 inches per 1 applicator.
    Pinch the wings or barrel on the applicator to break the ampule and release the antiseptic. Do not touch the sponge.
    Wet the sponge by repeated pressing and releasing the sponge against the treatment area until liquid is visible on the skin.
    Dry surgical sites (e.g., abdomen or arm): Apply using repeated back-and-forth strokes for 30 seconds.
    Moist surgical sites (e.g., inguinal fold): Apply using repeated back-and-forth strokes for 2 minutes.
    Do not allow solution to pool; use tuck prep towels to absorb and remove excess solution. Do not blot, as this may remove solution from skin.
    Applicators are single use only. After use, discard applicator and any remaining product.
     
    Betasept:
    Surgical hand scrub:
    Wet hands and forearms with warm water.
    Scrub for 3 minutes with approximately 5 mL of product and a wet sponge. Pay close attention to nails, cuticles, and interdigital spaces. A separate nail cleaner may be used.
    Rinse thoroughly.
    Wash for an additional 3 minutes with approximately 5 mL of product and rinse under running water.
    Dry thoroughly.
    Healthcare personnel hand wash:
    Wet hands with water.
    Dispense approximately 5 mL of product into cupped hands and wash in a vigorous manner for 15 seconds.
    Rinse and dry thoroughly.
    Patient preoperative skin preparation:
    Apply liberally to surgical site and swab for at least 2 minutes.
    Dry with a sterile towel.
    Repeat swabbing process for an additional 2 minutes, and dry with a sterile towel.
    Skin wound and general skin cleansing:
    Thoroughly rinse area to be cleansed with water.
    Apply the minimum amount of product necessary to cover the skin or wound area and wash gently.
    Rinse again thoroughly.
     
    Bactoshield sponge:
    Wet hands and forearms with warm water.
    Clean under nails with nail pick provided. Nails should be maintained with a 1 mm free edge.
    Wet sponge and squeeze to work up lather.
    Scrub for 3 minutes. Pay close attention to nails, cuticles, and interdigital spaces. Use the brush side to clean the interdigital spaces, and the sponge side to scrub the hands and forearms.
    Rinse thoroughly with warm water.
    Scrub for an additional 3 minutes using the sponge side, then rinse hands.
    Dry thoroughly. Discard brush-sponge.
     
    Hibiclens:
    Surgical hand scrub:
    Wet hands and forearms with warm water.
    Scrub for 3 minutes with approximately 5 mL of product and a brush.
    Rinse thoroughly under running water.
    Wash for an additional 3 minutes with approximately 5 mL of product and rinse under running water.
    Dry thoroughly.
    Healthcare personnel hand wash:
    Wet hands with water.
    Dispense approximately 5 mL of product into cupped hands and wash in a vigorous manner for 15 seconds.
    Rinse and dry thoroughly.
    Patient preoperative skin preparation:
    Apply liberally to surgical site and swab for at least 2 minutes.
    Dry with a sterile towel.
    Repeat swabbing process for an additional 2 minutes, and dry with a sterile towel.
    Skin wound and general skin cleansing:
    Thoroughly rinse area to be cleansed with water.
    Apply the minimum amount of product necessary to cover the skin or wound area and wash gently.
    Rinse again thoroughly.
     
    Prevantics maxi swabstick:
    Remove swabstick from package. Do not touch the foam tip.
    Place one flat side of foam tip to the proposed skin site and prep the skin in a vigorous back-and-forth motion for 1 minute.
    Turn the swabstick over and repeat the process for an additional 1 minute.
    Allow prepped area to dry for 1.5 minutes. Do not blot or wipe dry.
    Discard swabstick after a single use.
     
    Avagard:
    Surgical hand scrub:
    Apply to clean, dry hands and nails. For the first use of each day, clean under nails with a nail stick.
    Dispense 1 pump (2 mL) into the palm of 1 hand.
    Dip the fingertips of the opposite hand into the lotion and work it under the nails.
    Spread the remaining lotion over the hand and up to just above the elbow.
    Use another 2 mL of lotion to repeat the process with the other hand.
    Dispense another 2 mL of lotion into either hand; reapply to all aspects of both hands up to the wrists.
    Allow to dry before donning gloves.
    Healthcare personnel hand wash:
    Apply to clean, dry hands and nails.
    Dispense 1 pump (2 mL) into the palm of 1 hand.
    Paying particular attention to the spaces between the fingers and under fingernails, apply the lotion evenly to cover both hands up to the wrists.
    Allow to dry without wiping.

    Other Administration Route(s)

    Oral Rinse
    May be dispensed in the original container, which includes a measuring cup, or in an amber bottle with a device to measure 15 ml.
     
    Dental Implantation
    Assure the periodontal pocket and surrounding area are dry prior to implant insertion.
    Grasp the implant with forceps such that the rounded end points are away from the forceps.
    Insert the implant into the periodontal pocket to its maximum depth; may be maneuvered into position using the tips of the forceps or a flat instrument.
    The implants are biodegradable and do not need to be removed.
    If the implant becomes dislodged <= 48 hours after insertion, place a new implant. If the implant becomes dislodged 7 or more days after insertion, no replacement is needed. If the implant becomes dislodged > 48 hours after insertion, do not replace the implant, reevaluate the patient at 3 months and insert a new implant if the pocket depth is not < 5 mm.

    STORAGE

    Betasept:
    - Avoid excessive heat (above 104 degrees F)
    - Store between 68 to 77 degrees F
    Hibiclens:
    - Avoid excessive heat (above 104 degrees F)
    - Store between 68 to 77 degrees F
    Oro Clense :
    - Store and dispense in original container
    - Store between 68 to 77 degrees F, excursions permitted 59 to 86 degrees F
    Peridex:
    - Store and dispense in original container
    - Store between 68 to 77 degrees F, excursions permitted 59 to 86 degrees F
    Periogard:
    - Store and dispense in original container
    - Store between 68 to 77 degrees F, excursions permitted 59 to 86 degrees F
    PerioRx :
    - Store and dispense in original container
    - Store between 68 to 77 degrees F, excursions permitted 59 to 86 degrees F
    Perisol:
    - Store and dispense in original container
    - Store between 68 to 77 degrees F, excursions permitted 59 to 86 degrees F

    CONTRAINDICATIONS / PRECAUTIONS

    Breast-feeding

    It is not known if chlorhexidine is excreted into breast milk. However, chlorhexidine is poorly absorbed from the gastrointestinal tract even after oral use. In studies using chlorhexidine vaginally prior to delivery to prevent mother-to-child transmission of HIV, no adverse events were reported in any breast-fed infant. In a case report, a woman who was breast-feeding sprayed chlorhexidine on her breasts to prevent mastitis. Her 2-day old infant developed bradycardia following breast feeding. The bradycardia episodes resolved when the chlorhexidine was discontinued. However, in a study of 200 nursing mothers who sprayed their breasts with chlorhexidine in alcohol before and after each feeding, there were no reported side effects in any breast-fed infant. Consider the benefits of breast-feeding, the risk of potential drug exposure, and the risk of an untreated or inadequately treated condition. If a breast-feeding baby experiences an adverse effect related to a maternally administered drug, healthcare providers are encouraged to report the adverse effect to the FDA.

    Dental work

    Patients with dental work such as anterior tooth restorations (front-tooth fillings) or dentures may develop excessive and permanent discoloration of these areas after using chlorhexidine oral rinse. Replacement of fillings and appliances may be needed for cosmetic reasons. If natural stain cannot be removed from these appliances, consider avoiding treatment with chlorhexidine oral rinse due to increased risk of permanent staining. Anterior tooth restorations with rough surfaces or margins are at increased risk for staining and discretion should be used in these patients.

    Infection, periodontal disease

    The use of chlorhexidine in the management of patients with some types of periodontal disease should be carefully considered. For patients having coexisting gingivitis and periodontitis, the presence or absence of gingival inflammation following treatment with chlorhexidine oral rinse (e.g., Peridex) should not be used as a major indicator of underlying periodontitis; the effect of the oral rinse on periodontitis has not been determined. Chlorhexidine dental inserts (e.g., PerioChip) have not been studied in the treatment of acute abscessed periodontal pockets and are not recommended. Rarely, infections including abscesses and cellulitis, have been reported with the adjunctive use of PerioChip after scaling and root planing. Infection has been reported after scaling and root planing alone. Management of patients with periodontal disease should include consideration of potentially contributing medical disorders, such as cancer, diabetes, and immunocompromised status. Patients should notify the dentist promptly if pain, swelling, or other problems occur.

    Surgery

    When using topical solutions containing alcohol, including chlorhexidine, prior to surgery, be aware that the solution gives off flammable vapors. Do not drape or use ignition source such as cautery or laser until solution is completely dry (minimum of 3 minutes on hairless skin). Avoid applying solution into hairy areas because the solution may take much longer to dry or may not dry completely. Do not allow the solution to pool and remove wet materials from prep area.

    Ocular exposure

    Following ocular exposure of chlorhexidine topical antiseptic, serious and permanent eye injury has occurred during surgery when chlorhexidine enters and remains in the eye. Ocular effects include corneal edema, severe corneal endothelium damage requiring penetrating keratoplasty, iris atrophy, anterior chamber applanation (or flattening), and increased intraocular pressure. Inadvertent ocular exposure of chlorhexidine is characterized by streak formation in the anterior chamber.

    Pregnancy

    Chlorhexidine oral rise is pregnancy category B. However, adequate, well-controlled studies in pregnant women have not been done. Safety for use of topical chlorhexidine during pregnancy has not been established. Use only if clearly indicated and when the potential benefits are greater than the potential risks to the fetus.

    Tympanic membrane perforation

    In the presence of tympanic membrane perforation, take precautions to prevent exposure of inner ear tissues to chlorhexidine. Hearing loss and deafness may occur when chlorhexidine becomes in contact with the middle ear.

    Lumbar puncture, occlusive dressing, skin disease

    Chlorhexidine topical antiseptic should not be used in patients with skin disease or wounds involving more than the superficial layers of skin, or for repeated cleansing of large body areas except when it is necessary to reduce the bacteria population of the skin. Do not use under an occlusive dressing. Additionally, chlorhexidine should not be used to cleanse the skin prior to lumbar puncture; contact with the meninges should be avoided.

    Children, infants, neonates

    Topically administered chlorhexidine should be used with caution in premature infants, neonates and in infants less than 2 months of age because of the potential for irritation or chemical burns. The safety and efficacy of chlorhexidine oral rinse have not been established in neonates, infants, children, and adolescents.

    Risk of serious hypersensitivity reactions or anaphylaxis

    The rare risk of serious hypersensitivity reactions or anaphylaxis has been reported with the use of prescription and OTC products that contain chlorhexidine gluconate, including skin antiseptic products, dental products, and medical devices such as dressing and intravenous lines. Reactions can occur within minutes of exposure, and may include the following symptoms: wheezing or difficulty breathing, shock, facial swelling, hives, and rash. Allergic reactions may require emergency department visits or hospitalizations and have rarely resulted in death. PerioChip, is contraindicated in patients with a known sensitivity to chlorhexidine. Consider the use of alternative products in patients in which allergy to chlorhexidine is documented or suspected.

    Tobacco smoking

    Some chlorhexidine gluconate products are flammable. Avoid heat, flame, and tobacco smoking during and immediately following topical application.

    ADVERSE REACTIONS

    Severe

    anaphylactic shock / Rapid / Incidence not known
    anaphylactoid reactions / Rapid / Incidence not known
    angioedema / Rapid / Incidence not known

    Moderate

    gingival hyperplasia / Delayed / 2.3-3.6
    hypertension / Early / 2.2-2.7
    stomatitis / Delayed / 0-2.2
    erythema / Early / 0-1.0
    glossitis / Early / 0-1.0
    edema / Delayed / 0-1.0
    oral ulceration / Delayed / 0-1.0
    parotitis / Delayed / Incidence not known
    dyspnea / Early / Incidence not known
    wheezing / Rapid / Incidence not known

    Mild

    tooth discoloration / Delayed / 0-56.0
    dental pain / Delayed / 0-50.7
    infection / Delayed / 0-28.4
    headache / Early / 27.1-27.5
    sinusitis / Delayed / 13.1-13.8
    back pain / Delayed / 6.7-11.3
    influenza / Delayed / 7.6-9.5
    arthralgia / Delayed / 3.1-5.9
    myalgia / Early / 4.0-4.1
    pharyngitis / Delayed / 2.3-3.6
    rhinitis / Early / 2.7-3.2
    cough / Delayed / 2.7-3.2
    dyspepsia / Early / 2.7-3.1
    xerostomia / Early / 0-1.0
    paresthesias / Delayed / 0-1.0
    hypoesthesia / Delayed / 0-1.0
    gingivitis / Delayed / 0-1.0
    metallic taste / Early / Incidence not known
    calculus (tartar) formation / Delayed / Incidence not known
    urticaria / Rapid / Incidence not known
    rash / Early / Incidence not known
    skin irritation / Early / Incidence not known

    DRUG INTERACTIONS

    Disulfiram: (Minor) Some chlorhexidine oral rinses contain ethanol in significant percentages. Although chlorhexidine is poorly absorbed from the GI tract and the products are intended for oral topical rinse and not for systemic ingestion, there is a potential for interaction with disulfiram when such products are swallowed.

    PREGNANCY AND LACTATION

    Pregnancy

    Chlorhexidine oral rise is pregnancy category B. However, adequate, well-controlled studies in pregnant women have not been done. Safety for use of topical chlorhexidine during pregnancy has not been established. Use only if clearly indicated and when the potential benefits are greater than the potential risks to the fetus.

    It is not known if chlorhexidine is excreted into breast milk. However, chlorhexidine is poorly absorbed from the gastrointestinal tract even after oral use. In studies using chlorhexidine vaginally prior to delivery to prevent mother-to-child transmission of HIV, no adverse events were reported in any breast-fed infant. In a case report, a woman who was breast-feeding sprayed chlorhexidine on her breasts to prevent mastitis. Her 2-day old infant developed bradycardia following breast feeding. The bradycardia episodes resolved when the chlorhexidine was discontinued. However, in a study of 200 nursing mothers who sprayed their breasts with chlorhexidine in alcohol before and after each feeding, there were no reported side effects in any breast-fed infant. Consider the benefits of breast-feeding, the risk of potential drug exposure, and the risk of an untreated or inadequately treated condition. If a breast-feeding baby experiences an adverse effect related to a maternally administered drug, healthcare providers are encouraged to report the adverse effect to the FDA.

    MECHANISM OF ACTION

    Chlorhexidine destabilizes and penetrates bacterial cell membranes. Chlorhexidine precipitates the cytoplasm and interferes with membrane function by inhibiting oxygen utilization leading to a decrease in cellular ATP levels and cell death. In gram-negative bacteria, chlorhexidine affects the outer membrane allowing the release of periplasmic enzymes. The inner membrane of these organisms is not ruptured but the uptake of small molecules is impaired. At low concentrations chlorhexidine exhibits a bacteriostatic effect while at high concentrations it is bactericidal. The following organisms have a high susceptibility to chlorhexidine: some staphylococci, Streptococcus mutans, Streptococcus salivarius, Candida albicans, Escherichia coli, Selenomonas, and anaerobic propinionic bacteria. Streptococcus sanguis has moderate sensitivity to chlorhexidine. Proteus strains, Pseudomonas, Klebsiella, and gram-negative cocci resembling Veillonella have a low sensitivity to chlorhexidine. Chlorhexidine dental implants have shown a reduction in the numbers of Porphyromonas (Bacteriodes) gingivalis, Prevotella (Bacteriodes) intermedia, Bacteriodes forsythus, and Campylobacter rectus (Wolinella recta) after implant placement. During 6-month use of chlorhexidine oral rinse, dental plaque samples showed a 54—97% reduction in certain aerobic and anaerobic bacteria. Clinical studies have not shown any significant changes in bacterial resistance or overgrowth of opportunistic infections during treatment with chlorhexidine oral rinse or after placement of chlorhexidine implants. Chlorhexidine 5% (Hibitane(R) Concentrate - not available in the US) has been shown to be effective against rubella-, measles-, mumps- and HIV viruses and ineffective against roto-, polio-, rhino- and adeno-viruses. In addition, chlorhexidine is effective against cytomegalovirus and influenza virus.

    PHARMACOKINETICS

    Chlorhexidine is applied topically to the skin or is used as an oral rinse; it should never be ingested or used in the eye. Excretion is primarily via the feces and <1% is excreted in the urine.

    Oral Route

    After oral rinsing, chlorhexidine is adsorbed onto the surfaces of teeth, plaque and oral mucosa and is slowly released over a 24-hour period as the concentration of chlorhexidine decreases in the saliva. Approximately 30% of chlorhexidine gluconate remains in the oral cavity. In vitro, the dental implants release chlorhexidine from the matrix in a biphasic manner with approximately 40% released in the first 24 hours and then the remaining chlorhexidine is released linearly over the next 7—10 days. However, clinical studies show a high degree of interpatient variability in chlorhexidine release from the matrix. Chlorhexidine is poorly absorbed through the GI tract but may be absorbed following placement within a periodontal pocket. Following the placement of 4 implants, chlorhexidine plasma concentrations were at or below the limit of detection. The mean peak plasma concentration 30 minutes after inadvertent oral ingestion of chlorhexidine gluconate 300 mg was 0.206 mcg/mL.

    Topical Route

    After single application to intact skin, the residual concentration of chlorhexidine is higher than the MICs for most skin flora and some infectious organisms up to 24 hours after application. There is no evidence that chlorhexidine is absorbed through intact skin. For chlorhexidine topical antisepsis activity the optimal pH is 5.0—7.0, the normal pH of the skin.