Terbinafine Instructions for Jock Itch (Tinea Cruris)
Apply terbinafine 1% cream once daily for 1 week to the affected groin area, which achieves approximately 94% mycological cure rates and is the first-line treatment for patients ≥12 years old. 1, 2
Application Instructions
- Wash the affected skin with soap and water and dry completely before applying 2
- Apply once daily (morning or night) for 1 week 1, 2
- Use the tip of the cap to break the seal and open the tube 2
- Wash hands after each use 2
Age Restrictions
Critical Treatment Endpoint
The treatment endpoint must be mycological cure (negative microscopy and culture), not just clinical improvement, as clinical appearance may improve while infection persists. 1 This is a common pitfall—patients often stop treatment when symptoms resolve, but the fungus may still be present and can recur.
Superior Efficacy Profile
Terbinafine 1% cream demonstrates superior mycological cure rates (94%) with a significantly shorter treatment duration (1 week once daily) compared to clotrimazole (4 weeks twice daily). 1 This shorter duration improves compliance and reduces the risk of treatment failure due to premature discontinuation.
Prevention of Recurrence
To prevent autoinoculation and recurrence after successful treatment:
- Cover active tinea pedis (athlete's foot) lesions with socks before wearing underwear 1
- Completely dry the crural folds after bathing 1
- Avoid skin-to-skin contact with infected individuals 1
- Do not share towels and other personal items that could serve as fomites 3
When to Consider Oral Therapy
For extensive tinea cruris or cases with poor response to topical therapy after 1 week, oral itraconazole (100 mg daily for 2 weeks or 200 mg daily for 1 week) is effective in adults. 1 Oral terbinafine 250 mg once daily for 2-4 weeks is another option for patients over 40 kg. 3
Safety Considerations
Oral terbinafine is contraindicated in active or chronic liver disease, lupus erythematosus, and porphyria. 1 Monitor for occasional isolated neutropenia and rare liver failure, particularly in patients with preexisting liver disease. 1