What is the recommended treatment for a patient with Tinea curis (jock itch) on the buttock?

Treatment of Tinea Cruris on the Buttock

Apply terbinafine 1% cream once daily for 1 week, which achieves approximately 94% mycological cure rates and is FDA-approved for jock itch (tinea cruris). 1, 2

First-Line Topical Treatment

• Terbinafine 1% cream applied once daily for 1 week is the preferred initial treatment for tinea cruris, including lesions extending to the buttock area 1, 3, 2
• The FDA label specifically indicates terbinafine cures most jock itch (tinea cruris) and relieves associated itching, burning, cracking and scaling 2
• Wash the affected skin with soap and water and dry completely before applying the medication 2
• This regimen is approved for patients 12 years and older 1, 3, 2

Alternative Topical Options

• Butenafine cream applied twice daily for 2 weeks is an effective over-the-counter alternative, though only approved for adults 1, 3
• Clotrimazole 1% cream applied twice daily for 2-4 weeks can be used, with a mycological cure rate showing superiority over placebo (RR 2.87) 1, 4

When to Escalate to Oral Therapy

Consider oral antifungals if:

• The infection is resistant to topical treatment after completing the full course 4
• The infection is extensive or involves multiple body sites 1
• The patient is immunocompromised 5

Oral Treatment Regimens

• Terbinafine 250 mg daily for 1-2 weeks is highly effective, particularly against Trichophyton species, with rapid clinical resolution 1, 3, 6
• Itraconazole 100 mg daily for 15 days achieves 87% mycological cure rate and is effective against both Trichophyton and Microsporum species 1, 4, 3, 7
• Itraconazole 200 mg daily for 7 days offers a shorter, more convenient option with 90% mycological cure rates 7

Critical Prevention Measures to Prevent Recurrence

Address concurrent tinea pedis aggressively, as foot infections commonly contaminate the groin and buttock area through clothing 3

• Put on socks before underwear to cover any active foot lesions and prevent direct contamination of the groin area 1, 3
• Completely dry the groin folds and buttock area after bathing before getting dressed 1, 3
• Use separate clean towels for drying the groin versus other body parts to reduce contamination risk 1, 3
• Screen and treat household contacts, as over 50% of family members may harbor infection with anthropophilic species like Trichophyton tonsurans 4, 3
• Clean all contaminated items (towels, clothing, bedding) with disinfectant or 2% sodium hypochlorite solution 4, 3

Treatment Monitoring and Endpoints

• Continue treatment for at least one week after clinical clearing to ensure mycological cure, not just symptomatic improvement 3
• Mycological cure (negative microscopy and culture) must be the definitive treatment endpoint, not just clinical improvement 4, 5, 3
• If symptoms return after initial improvement, this indicates ongoing fungal presence requiring extended treatment duration 3

Important Safety Considerations

• Baseline liver function tests are recommended before initiating oral terbinafine or itraconazole, especially with pre-existing hepatic abnormalities 4, 5
• Terbinafine's most concerning potential adverse events include occasional isolated neutropenia and rare liver failure, typically in people with preexisting liver disease 1
• Itraconazole has significant drug interactions with warfarin, certain antihistamines, antipsychotics, midazolam, digoxin, and simvastatin 4, 5

Common Pitfalls to Avoid

• Do not stop treatment when symptoms improve clinically - continue until mycological cure is achieved to prevent relapse 4, 5, 3
• Do not ignore concurrent tinea pedis - failure to treat foot infections simultaneously is a major cause of groin infection recurrence 3
• Do not use topical steroid-antifungal combinations as first-line therapy - while they may provide faster symptomatic relief, guidelines do not currently recommend them, and they may mask ongoing infection 8