Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
EXSEL vs EXELDERM
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.
Topical antimycotic that inhibits fungal squalene epoxidase, leading to accumulation of squalene and disruption of fungal cell wall synthesis.
Treatment of tinea versicolor (pityriasis versicolor),Management of dandruff and seborrheic dermatitis of the scalp
Tinea pedis,Tinea cruris,Tinea corporis,Tinea versicolor
1-2 mg orally once daily; maximum dose 2 mg/day.
Apply a thin layer to affected skin twice daily (morning and evening).
Terminal half-life: 12-18 hours (mean 15 h); requires dose adjustment in renal impairment (Cr Cl <30 m L/min).
Not applicable due to negligible systemic absorption; after topical application, half-life in skin is several hours.
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; when absorbed, primarily metabolized in the liver via oxidation and glucuronidation.
Renal: ~70% unchanged; biliary/fecal: ~30% as metabolites.
Systemic absorption is minimal; any absorbed sulconazole is primarily metabolized in the liver and excreted in feces via bile; renal excretion of unchanged drug is negligible.
95% bound to albumin and alpha-1-acid glycoprotein.
Not applicable; systemic levels are undetectable with topical use.
0.8-1.2 L/kg; indicates extensive extravascular distribution.
Not applicable; negligible systemic absorption.
Oral: 60-80%; first-pass metabolism reduces bioavailability by 20-40%.
Topical: negligible systemic bioavailability (<1%) due to poor percutaneous absorption.
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.
Safety and efficacy in pediatric patients below 12 years have not been established; see prescribing information for age-specific recommendations.
Start at 1 mg orally once daily; titrate cautiously due to increased risk of falls and hypotension.
No specific geriatric dose adjustments; use caution due to higher risk of adverse effects from prolonged use.
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.
Avoid contact with eyes, nose, mouth, or other mucous membranes. Discontinue if irritation or sensitization occurs. Not for oral or ophthalmic use. Use in children under 12 years not established.
Hypersensitivity to selenium sulfide or any component of the formulation. Do not use on broken or inflamed skin.
Known hypersensitivity to sulconazole or any component of the formulation.
No known food interactions.
None known.
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.
Category B: No teratogenic effects in animal studies; no adequate human studies in first trimester. Avoid use in first trimester unless clearly needed.
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.
Not known if excreted in breast milk. Caution in nursing mothers; limited data. M/P ratio not available.
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 use; insufficient data for systemic absorption changes.
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.
Apply sparingly to affected area; avoid use on mucous membranes or intertriginous areas. Discontinue if irritation occurs. Not recommended for use under occlusive dressings.
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.
Use only on the skin as directed; avoid contact with eyes, mouth, or open wounds.,Wash hands before and after applying unless treating hands.,Do not cover the treated area with bandages or wrappings unless directed by a doctor.,Stop use and consult doctor if condition worsens or does not improve within 2 weeks.,Inform your doctor if you are pregnant, planning to become pregnant, or breastfeeding.
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 EXELDERM, 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.. EXELDERM is a Topical Antifungal that works by Topical antimycotic that inhibits fungal squalene epoxidase, leading to accumulation of squalene and disruption of fungal cell wall synthesis.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between EXSEL and EXELDERM 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 EXELDERM is: Apply a thin layer to affected skin twice daily (morning and evening).. 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 EXELDERM 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. EXELDERM is classified as Category C. Category B: No teratogenic effects in animal studies; no adequate human studies in first trimester. Avoid use in first trimester unless clearly needed.. Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.