Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
EXSEL vs LOTRIMIN AF
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
Exsel (selenium sulfide) is an antifungal agent that reduces the production of cutaneous oils and exerts cytostatic effects on epidermal cells. It inhibits the growth of Pityrosporum ovale and other fungi by interfering with oxidative enzyme systems, leading to decreased sebum production and normalization of epidermal turnover.
Inhibits fungal cytochrome P450 14α-demethylase, blocking ergosterol synthesis and disrupting fungal cell membrane integrity.
Treatment of tinea versicolor (pityriasis versicolor),Management of dandruff and seborrheic dermatitis of the scalp
Tinea pedis,Tinea cruris,Tinea corporis,Pityriasis versicolor,Cutaneous candidiasis
1-2 mg orally once daily; maximum dose 2 mg/day.
Topical: Apply twice daily (morning and evening) to affected area for 2-4 weeks. Intravaginal: One 200 mg suppository vaginally at bedtime for 3 days, or one 500 mg vaginal tablet as a single dose.
Terminal half-life: 12-18 hours (mean 15 h); requires dose adjustment in renal impairment (Cr Cl <30 m L/min).
Terminal elimination half-life of absorbed clotrimazole is approximately 3.5–4 hours, but this is clinically irrelevant due to negligible systemic absorption after topical application.
Minimal systemic absorption after topical application; any absorbed selenium is primarily excreted in urine, with minor metabolism via reduction to selenides and methylation to dimethylselenide.
Minimal systemic absorption; primarily local metabolism.
Renal: ~70% unchanged; biliary/fecal: ~30% as metabolites.
Less than 1% of topical clotrimazole is absorbed; absorbed drug is metabolized in the liver to inactive metabolites and excreted primarily in feces (approximately 69%) and urine (approximately 21%) via biliary and renal routes.
95% bound to albumin and alpha-1-acid glycoprotein.
Approximately 90–95% bound to plasma proteins, primarily albumin.
0.8-1.2 L/kg; indicates extensive extravascular distribution.
Vd is approximately 2.5 L/kg after intravenous administration (data for systemic formulation); after topical application, systemic absorption is negligible (<1%), so Vd is not clinically meaningful.
Oral: 60-80%; first-pass metabolism reduces bioavailability by 20-40%.
Topical: Systemic bioavailability is <1% after application to intact skin; vaginal tablet: approximately 3–10% absorbed systemically.
No adjustment required for mild to moderate impairment. Severe impairment (GFR <30 m L/min): contraindicated.
No dosage adjustment required for renal impairment.
Child-Pugh A: no adjustment. Child-Pugh B or C: contraindicated.
No dosage adjustment required for hepatic impairment.
Not recommended for use in pediatric patients due to lack of safety and efficacy data.
Children ≥2 years: Same as adult dosing for topical application. Children <2 years: Not recommended without physician consultation.
Start at 1 mg orally once daily; titrate cautiously due to increased risk of falls and hypotension.
No specific dose adjustment; use same adult dosing with consideration of renal/hepatic function and potential drug interactions.
None.
None
Avoid contact with eyes, eyelids, and mucous membranes. If contact occurs, rinse thoroughly with water. Discontinue if local irritation or sensitization develops. Use with caution in patients with inflamed or broken skin due to increased absorption risk. Not for use on large areas of the body for prolonged periods.
For external use only,Avoid contact with eyes,Discontinue if irritation occurs,Not for vaginal or oral use
Hypersensitivity to selenium sulfide or any component of the formulation. Do not use on broken or inflamed skin.
Hypersensitivity to clotrimazole or any component
No known food interactions.
No clinically significant food interactions for topical clotrimazole.
Pregnancy Category D. First trimester: Associated with Ebstein's anomaly and other congenital heart defects; avoid if possible. Second and third trimesters: Risk of fetal hyperthyroidism or hypothyroidism, cranial synostosis, intellectual disability, and neonatal goiter if maternal hyperthyroidism is treated with this drug. Use only if clearly needed and maternal benefit outweighs fetal risk.
Clotrimazole (Lotrimin AF) is category B. No evidence of teratogenicity in animal studies. Limited human data from topical use in first trimester show no increased risk of major malformations. Systemic absorption from topical application is minimal (<0.5%), making fetal exposure negligible. No known fetal risks from topical use in any trimester.
Excreted in human milk. M/P ratio not available. Potential for serious adverse reactions in nursing infants, including thyroid dysfunction and arrhythmias. Decision to discontinue nursing or drug based on importance of drug to mother.
Topical clotrimazole is considered compatible with breastfeeding. Systemic absorption is minimal, and any excreted amounts in breast milk are negligible. M/P ratio is not available due to minimal absorption. Avoid application to breast area to prevent infant oral contact.
Pregnancy may increase clearance of this drug; dose adjustments often not required, but individualize based on maternal thyroid function and clinical response. Lower doses may be needed to avoid fetal hypothyroidism.
No dose adjustment required for topical clotrimazole during pregnancy. Pharmacokinetics are not significantly altered as systemic absorption is minimal. Use standard dosing for indication (e.g., 1% cream twice daily for 2-4 weeks for dermatophytosis).
EXSEL (selenium disulfide) 2.5% shampoo: Use twice weekly for 2 weeks, then once weekly for maintenance. Limit application to 5-10 minutes before rinsing. Avoid contact with eyes or broken skin. Can cause temporary hair discoloration (especially on bleached or permed hair). May stain jewelry and clothing. For dandruff and seborrheic dermatitis of the scalp.
Lotrimin AF (clotrimazole) is a topical antifungal used for dermatophyte and yeast infections. For tinea pedis, apply twice daily for 4 weeks; shorter courses may lead to recurrence. Do not use in or near eyes. Avoid occlusive dressings unless directed.
Shake bottle well before use.,Wet hair thoroughly before applying shampoo.,Apply enough shampoo to lather and massage into scalp for 2-3 minutes.,Leave on scalp for 5 minutes (up to 10 minutes) before rinsing thoroughly.,Rinse hair and scalp completely to avoid residue.,Use twice weekly for first 2 weeks, then once weekly as directed.,Avoid contact with eyes; if contact occurs, rinse thoroughly with water.,Do not use on broken or irritated skin.,Discontinue use and consult doctor if rash or irritation develops.,May stain clothing and jewelry; rinse thoroughly after use.
Apply a thin layer to affected skin twice daily, morning and evening.,Wash hands before and after application unless treating hands.,Continue use for the full prescribed duration even if symptoms improve.,Avoid contact with eyes, mouth, or open wounds.,Do not cover treated area with bandages or plastic unless instructed.
No interactions on record
No interactions on record
Explore head-to-head clinical comparisons of other medications in the same therapeutic classes.
Common clinical questions about EXSEL vs LOTRIMIN AF, answered by our medical review team.
EXSEL is a Topical Antifungal that works by Exsel (selenium sulfide) is an antifungal agent that reduces the production of cutaneous oils and exerts cytostatic effects on epidermal cells. It inhibits the growth of Pityrosporum ovale and other fungi by interfering with oxidative enzyme systems, leading to decreased sebum production and normalization of epidermal turnover.. LOTRIMIN AF is a Topical Antifungal that works by Inhibits fungal cytochrome P450 14α-demethylase, blocking ergosterol synthesis and disrupting fungal cell membrane integrity.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between EXSEL and LOTRIMIN AF depend on the specific clinical indication. These are both Topical Antifungal agents and are not directly interchangeable by dose. A physician or clinical pharmacist should guide any therapeutic switching decisions.
The standard adult dose of EXSEL is: 1-2 mg orally once daily; maximum dose 2 mg/day.. The standard adult dose of LOTRIMIN AF is: Topical: Apply twice daily (morning and evening) to affected area for 2-4 weeks. Intravaginal: One 200 mg suppository vaginally at bedtime for 3 days, or one 500 mg vaginal tablet as a single dose.. Dosing should always be individualized based on indication, renal and hepatic function, age, and other patient factors.
No direct drug-drug interaction has been formally documented between EXSEL and LOTRIMIN AF in current clinical databases. However, individual patient risk factors including other medications, organ function, and comorbidities should always be evaluated by a qualified healthcare provider.
The maternal-fetal safety profiles differ. EXSEL is classified as Category C. Pregnancy Category D. First trimester: Associated with Ebstein's anomaly and other congenital heart defects; avoid if possible. Second and third trimesters: Risk of fetal hyperthyr. LOTRIMIN AF is classified as Category C. Clotrimazole (Lotrimin AF) is category B. No evidence of teratogenicity in animal studies. Limited human data from topical use in first trimester show no increased risk of major ma. Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.