Fluconazole Dosing for Fungal Rash
For cutaneous fungal infections (tinea corporis, tinea cruris, or other dermatophyte infections), fluconazole 150 mg once weekly for 2-4 weeks is the recommended approach, though a single 150 mg dose may suffice for mild cases. 1
Dosing by Type of Cutaneous Fungal Infection
Dermatophyte Infections (Tinea)
- Tinea corporis/cruris: Start with fluconazole 150 mg as a single dose, then reassess at 7 days 1
- If not improved or cured at 7 days, give additional 150 mg doses weekly until resolution (maximum 4 doses total) 1
- Most patients with tinea corporis/cruris require 2 doses (70%), with 95% achieving clinical and mycological cure 1
- Tinea pedis: Typically requires 3-4 weekly doses of 150 mg (60% of patients need all 4 doses), with 70% cure rate and 30% showing improvement 1
Cutaneous Candidiasis
- Mild to moderate cutaneous candidiasis: Fluconazole 50-150 mg daily for several weeks to months achieves over 90% clinical cure or improvement 2
- Severe cutaneous candidiasis: Consider fluconazole 100-200 mg daily for 7-14 days, similar to oropharyngeal dosing 3
Important Clinical Considerations
Treatment Duration
- Continue treatment for at least 2 weeks even if symptoms resolve earlier to reduce relapse risk 4
- Cutaneous mycoses generally require weeks to months of therapy depending on severity and location 2
- Monitor clinical response at 7-day intervals and add additional doses as needed 1
When to Consider Alternative Diagnoses
- If no improvement after 2-3 doses of fluconazole 150 mg weekly, consider non-dermatophyte causes or resistant organisms 1
- Obtain fungal culture and susceptibility testing if treatment fails 3
Critical Pitfalls to Avoid
- Do not use fluconazole prophylactically for simple antibiotic courses in immunocompetent patients, as this promotes resistance without benefit 5
- Inadequate treatment duration is the most common cause of relapse—complete the full course even after clinical improvement 3
- Avoid topical-only therapy for extensive or severe cutaneous infections, as systemic therapy is more effective 2
- For immunocompromised patients with cutaneous candidiasis, expect higher relapse rates (40%) and consider chronic suppressive therapy with fluconazole 100 mg three times weekly 3, 5