What is the recommended treatment for tinea cruris?

Treatment of Tinea Cruris

For uncomplicated tinea cruris, use terbinafine 1% cream applied once daily for 1 week as first-line therapy, which achieves a ~94% mycological cure rate. 1

First-Line Topical Treatment

• Terbinafine 1% cream once daily for 1 week is the preferred initial treatment based on American Academy of Pediatrics recommendations, offering high efficacy with the shortest treatment duration. 1
• This regimen is FDA-approved for patients 12 years and older. 1
• The mycological cure rate approaches 94%, making it superior to most other topical options. 2

Alternative Topical Options

If terbinafine is unavailable or contraindicated, consider these alternatives:

• Butenafine applied twice daily for 2 weeks is an effective over-the-counter option for adults (not approved for children). 1, 2
• Clotrimazole applied twice weekly for 4 weeks provides another proven alternative, though requires longer treatment duration. 1, 2
• Econazole cream is FDA-approved for tinea cruris and can be applied as directed. 3

When to Use Oral Therapy

Systemic treatment is indicated when:

• The infection is severe or extensive 2
• Topical therapy has failed 2
• The patient has tinea cruris incognito (modified by prior steroid use) 4

For severe cases requiring oral therapy:

• Itraconazole 100 mg daily for 2 weeks OR 200 mg daily for 1 week is the most effective systemic option, superior to griseofulvin and active against both Trichophyton and Microsporum species. 2, 4
• Oral terbinafine 250 mg daily for 1 week (adults) is highly effective, with weight-based dosing for children: <20 kg: 62.5 mg/day; 20-40 kg: 125 mg/day; >40 kg: 250 mg/day. 4, 5
• Fluconazole 150 mg once weekly for 2-4 weeks serves as an alternative when other treatments are contraindicated. 2, 6

Critical Pitfalls to Avoid

• Treatment failure often results from poor compliance, inadequate medication absorption, or organism resistance. 1
• If clinical improvement occurs but mycology remains positive, continue current therapy for an additional 2-4 weeks rather than switching agents prematurely. 1
• Never use topical steroids alone or in combination for initial treatment of suspected tinea cruris, as this creates tinea incognito, which is more resistant and requires systemic therapy. 4
• Griseofulvin is inferior to itraconazole and should not be considered first-line. 2

Essential Prevention Strategies

• Complete drying of the crural folds after bathing is critical to prevent recurrence. 1, 2
• Use separate towels for drying the groin versus other body parts to reduce contamination. 1, 2
• Cover active foot lesions (tinea pedis) with socks before putting on underwear to prevent direct contamination. 1, 2
• Address predisposing factors including obesity and diabetes, which increase risk. 2, 4

Treatment Duration Considerations

• For topical therapy, continue treatment for at least 1 week after clinical clearing to ensure mycological cure. 7
• Standard tinea cruris treatment duration is 2 weeks for most topical agents, though terbinafine requires only 1 week. 1, 7
• For tinea cruris incognito, extend treatment 1-2 weeks beyond clinical resolution. 4