DefinitionJock itch, also called tinea cruris or ringworm of the groin, is an infection of the groin area caused by fungus.
Alternative NamesFungal infection - groin; Infection - fungal - groin; Itching in the groin; Ringworm - groin; Tinea cruris; Tinea of the groin
Causes, incidence, and risk factorsJock itch occurs when a particular type of fungus grows and spreads in the groin area.Jock itch occurs mostly in adult men and adolescent boys. It can sometimes accompany athlete's foot and ringworm. The fungus that causes jock itch thrives in warm, moist areas.Jock itch can be triggered by friction from clothes and prolonged wetness in the groin area, such as from sweating.Jock itch may be contagious. It can be passed from one person to the next by direct skin-to-skin contact or contact with unwashed clothing.
SymptomsItching in groin, thigh skin folds, or anusRed, raised, scaly patches that may blister and ooze -- The patches often have sharply-defined edges and are often redder around the outside with normal skin tone in the centerAbnormally dark or light skin
Signs and testsYour health care provider can usually diagnose jock itch based on how your skin looks.Tests are usually not necessary. If tests are needed to confirm the diagnosis, either a culture or a skin lesion biopsy (for example, a scraping of the skin) may be done. A KOH (potassium hydroxide) test may be done in the office for quick diagnosis.
TreatmentJock itch usually responds to self-care within a couple of weeks:Keep the skin clean and dry.Don't wear clothing that rubs and irritates the area.Apply topical over-the-counter antifungal or drying powders, such as those that contain miconazole, clotrimazole, or tolnaftate.You may need treatment by a health care provider if your infection lasts longer than 2 weeks, is severe, or frequently returns. You healthcare provider may prescribe stronger antifungal medications. Antibiotics may be prescribed to treat bacterial infections that occur in addition to the fungus (for example, from scratching the area).
Expectations (prognosis)Jock itch usually responds promptly to treatment. It is often less severe than other tinea infections, but may last a long time.Jock itch usually stays around the creases in the upper thigh and does not involve the scrotum or penis. Jock itch may spread to the anus, causing anal itching and discomfort.Other causes of itching in the groin include:Lichen simplex chronicusEczemaPubic liceChemical irritationSee also: Vaginal itching
ComplicationsPermanent change in the skin color of the area
Secondary bacterial skin infections
Side effects of medications
Calling your health care providerCall your doctor if jock itch does not respond to home care after 2 weeks, or you have other symptoms.
PreventionKeep the groin area clean and dry.
Don't wear clothing that rubs and irritates the area. Avoid tight-fitting and rough-textured clothing.
Wear loose-fitting underwear.
Wash athletic supporters frequently.
After bathing, apply antifungal or drying powders if you are susceptible to jock itch.
ReferencesAndrews MD, Burns M. Common tinea infections in children. Am Fam Physician. 2008;77:1415-1420.