Fluconazole Dosing for Ringworm
For ringworm (tinea corporis/cruris), fluconazole should be administered at 150 mg once weekly for 2-4 weeks. 1, 2, 3
Treatment Regimen Details
Ringworm (dermatophytosis) is a superficial fungal infection that responds well to systemic antifungal therapy with fluconazole. The recommended dosing is:
- Dose: 150 mg fluconazole
- Frequency: Once weekly
- Duration: 2-4 weeks (depending on severity and clinical response)
This regimen has been shown to be both efficacious and safe, with clinical studies demonstrating high cure rates (85-92%) for tinea corporis and tinea cruris with this dosing schedule 1, 3.
Evidence Supporting This Recommendation
Multiple clinical studies support the once-weekly dosing approach:
A study by Montero-Gei et al. showed that fluconazole 150 mg once weekly for 2-4 weeks reduced total severity scores of clinical symptoms from 7.1 to 1.5 (p=0.001) in patients with tinea corporis and cruris 1.
Another study demonstrated that with once-weekly 150 mg fluconazole dosing, 88% of patients achieved clinical cure at long-term follow-up, with only 11% experiencing mycological relapse 3.
The efficacy of this regimen is attributed to fluconazole's pharmacokinetic properties, including its long half-life (31.4 ± 4.7 hours in healthy individuals) and excellent tissue distribution 4.
Treatment Algorithm Based on Infection Site
Tinea corporis (body ringworm):
- 150 mg fluconazole once weekly for 2-3 weeks
- Lower relapse rate (approximately 3%) compared to tinea cruris 3
Tinea cruris (groin ringworm):
- 150 mg fluconazole once weekly for 3-4 weeks
- May require longer treatment due to higher relapse rate (approximately 12%) 3
Important Clinical Considerations
Treatment failure: If clinical improvement is not evident after the initial dose, continue weekly dosing for the full 4-week course before considering alternative treatments.
Monitoring: No routine laboratory monitoring is required for short-term therapy in healthy individuals.
Common pitfalls to avoid:
- Discontinuing treatment prematurely once symptoms improve
- Failing to treat all affected areas, which can lead to reinfection
- Not addressing potential sources of reinfection (clothing, bedding, etc.)
Special Populations
Children: For pediatric tinea capitis, fluconazole 6 mg/kg daily has been studied but showed comparable but relatively low cure rates to standard-dose griseofulvin 5.
Immunocompromised patients: May require longer treatment duration and closer follow-up, with systemic therapy often preferred over topical agents 6.
This once-weekly dosing regimen offers excellent patient compliance advantages while maintaining high efficacy rates for the treatment of ringworm infections.