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Tinea Cruris (Jock Itch)


Denise M. Aaron

, MD, Dartmouth Geisel School of Medicine

Reviewed/Revised Sep 2021 | Modified Sep 2022
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Tinea cruris is a dermatophyte infection of the groin. Diagnosis is by clinical appearance and by potassium hydroxide wet mount. Treatment is with topical antifungals.

Tinea cruris is a dermatophytosis Overview of Dermatophytoses Dermatophytoses are fungal infections of keratin in the skin and nails (nail infection is called tinea unguium or onychomycosis). Symptoms and signs vary by site of infection. Diagnosis is by... read more that is commonly caused by Trichophyton rubrum or T. mentagrophytes. The primary risk factors are associated with a moist environment (ie, warm weather, wet and restrictive clothing, obesity causing constant apposition of skinfolds). Men are affected more than women because of apposition of the scrotum and thigh.

Typically, a pruritic, ringed lesion extends from the crural fold over the adjacent upper inner thigh. Infection may be bilateral. Lesions may be complicated by maceration, miliaria, secondary bacterial or candidal infection, and reactions to treatment. In addition, scratch dermatitis and lichenification can occur. Recurrence is common because fungi may repeatedly infect susceptible people or people with onychomycosis Onychomycosis Onychomycosis is fungal infection of the nail plate, nail bed, or both. The nails typically are deformed and discolored white or yellow. Diagnosis is by appearance, wet mount, culture, polymerase... read more Onychomycosis or tinea pedis Tinea Pedis (Athlete's Foot) Tinea pedis is a dermatophyte infection of the feet. Diagnosis is by clinical appearance and sometimes by potassium hydroxide wet mount, particularly if the infection manifests as hyperkeratotic... read more Tinea Pedis (Athlete's Foot) , which can serve as a dermatophyte reservoir. Flare-ups occur more often during summer.

Diagnosis of Tinea Cruris

  • Clinical evaluation

  • Potassium hydroxide wet mount

Scrotal involvement is usually absent or slight; by contrast, the scrotum is often inflamed in candidal intertrigo or lichen simplex chronicus. If the appearance is not diagnostic, a potassium hydroxide wet mount is helpful.

Differential diagnosis of tinea cruris includes

Treatment of Tinea Cruris

  • Topical antifungal cream, lotion, or gel

Antifungal choices include terbinafine, miconazole, clotrimazole, ketoconazole, econazole, naftifine, and (uncommonly) ciclopirox applied 2 times a day for 10 to 14 days.

Itraconazole 200 mg orally once a day or terbinafine 250 mg orally once a day for 3 to 6 weeks may be needed in patients who have refractory, inflammatory, or widespread infections.

Key Points

  • Suspect tinea cruris when pruritic, ringed lesions extend from the crural fold over the adjacent upper inner thigh, particularly in obese patients or men.

  • Topical terbinafine, miconazole, clotrimazole, ketoconazole, econazole, or naftifine 2 times a day for 10 to 14 days is usually effective.

Drugs Mentioned In This Article

Drug Name Select Trade
Desenex Max, Lamisil, Lamisil AT, Lamisil AT Athletes Foot, Lamisil AT Jock Itch, Terbinex
Alevazol , Antifungal, Anti-Fungal, Cruex, Desenex, Fungoid, Gyne-Lotrimin, Lotrimin, Lotrimin AF, Lotrimin AF Ringworm, Micotrin AC, Mycelex, Mycelex Troche, Mycozyl AC
Extina, Ketodan, Kuric, Nizoral, Nizoral A-D, Xolegel
Ecoza, Spectazole, Zolpak
Naftin, Naftin-MP
Ciclodan, Ciclodan Nail Solution, Loprox, Loprox TS, Penlac
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