MYCELEX
Clinical safety rating: caution
Comprehensive clinical and safety monograph for MYCELEX (MYCELEX).
Clotrimazole, an imidazole antifungal, inhibits fungal cytochrome P450 14α-demethylase, thereby disrupting ergosterol biosynthesis and compromising fungal cell membrane integrity.
| Metabolism | Clotrimazole is extensively metabolized in the liver via cytochrome P450 enzymes, primarily CYP3A4, to inactive metabolites. |
| Excretion | Primarily hepatic metabolism; <1% excreted unchanged in urine; ~50% of dose excreted in feces as metabolites. |
| Half-life | Terminal elimination half-life is 20-50 hours (mean ~30 hours) in adults; prolonged in neonates (~40-80 hours) and in hepatic impairment. |
| Protein binding | 92-95% bound to plasma proteins, primarily albumin. |
| Volume of Distribution | 0.12-0.24 L/kg; indicates limited tissue distribution, primarily confined to extracellular fluid. |
| Bioavailability | Topical (vaginal): Minimal systemic absorption (<10%); oral troche: Negligible systemic absorption due to local action. |
| Onset of Action | Topical (vaginal cream/suppository): Symptomatic relief begins within 24-72 hours. Oral troche: Not applicable for systemic effect; local mucosal action onset within hours. |
| Duration of Action | Topical: Therapeutic effect persists for the duration of treatment (usually 3-7 days); single-dose vaginal tablet maintains therapeutic concentrations for up to 72 hours. |
For oropharyngeal candidiasis: Clotrimazole troche 10 mg dissolved slowly in mouth 5 times daily for 14 days. For vulvovaginal candidiasis: Clotrimazole vaginal tablet 500 mg single dose or 200 mg daily for 3 days or 100 mg daily for 7 days; 1% vaginal cream 5 g intravaginally daily for 7-14 days.
| Dosage form | Solution |
| Renal impairment | No dosage adjustment required for renal impairment. |
| Liver impairment | No specific dosage adjustment recommended; use with caution in severe hepatic impairment. |
| Pediatric use | For oropharyngeal candidiasis in children ≥3 years: Clotrimazole troche 10 mg dissolved slowly in mouth 5 times daily for 14 days. For vulvovaginal candidiasis in adolescents: same as adult dosing. Safety and efficacy in children <3 years not established. |
| Geriatric use | No specific dosage adjustment; use with caution due to potential for decreased salivary flow affecting troche dissolution. |
| 1st trimester | Consult provider |
| 2nd trimester | Consult provider |
| 3rd trimester | Consult provider |
Clinical note
Comprehensive clinical and safety monograph for MYCELEX (MYCELEX).
| Breastfeeding | Unknown if excreted in human milk. M/P ratio not determined. Although systemic absorption is minimal, caution should be exercised. Consider risk-benefit. |
| Teratogenic Risk | FDA Pregnancy Category C. No adequate studies in pregnant women. In animal studies, no teratogenic effects observed at topical doses up to 100 mg/kg/day. Systemic absorption from topical application is minimal, but in first trimester, use only if clearly needed. In second and third trimesters, risk is low but avoid if possible. |
| Fetal Monitoring |
■ FDA Black Box Warning
None.
| Serious Effects |
Hypersensitivity to clotrimazole or any component of the formulation.
| Precautions | Hepatic impairment: monitor liver function; hypersensitivity reactions; for intravaginal use, discontinue if irritation or sensitization occurs; not for ophthalmic use. |
Loading safety data…
| No specific monitoring required for topical use. For systemic use, monitor liver function tests, renal function, and complete blood count due to potential hepatotoxicity and bone marrow suppression. |
| Fertility Effects | No known effects on fertility in humans. In animal studies, no impairment of fertility at doses up to 100 mg/kg/day. |