Jock itch (tinea cruris) is a fungal infection that causes a red and itchy rash in warm and moist areas of the body. The rash often affects the groin and inner thighs and may be shaped like a ring.
Jock itch gets its name because it's common in athletes. It's also common in people who sweat a lot or who are overweight.
Although often uncomfortable and bothersome, jock itch usually isn't serious. Treatment may involve keeping the groin area clean and dry and applying topical antifungal medications to the affected skin.
Jock itch usually begins with a reddened area of skin in the crease in the groin. It often spreads to the upper thigh in a half-moon shape. The rash may be ring-shaped and bordered with a line of small blisters. It may burn or feel itchy, and the skin may be flaky or scaly.
See your doctor if your rash is painful or you develop a fever. And see your doctor if the rash hasn't improved after a week of treatment or if it hasn't cleared up completely after three weeks of treatment.
The organisms that cause jock itch thrive in damp, close environments. Jock itch is caused by a fungus that spreads from person to person or from sharing contaminated towels or clothing. It's often caused by the same fungus that causes athlete's foot. The infection often spreads from the feet to the groin because the fungus can travel on your hands or on a towel.
You're at greater risk of jock itch if you:
Reduce your risk of jock itch by taking these steps:
Your doctor can often diagnose jock itch by looking at the rash. If the diagnosis isn't clear-cut, your doctor may take skin scrapings or samples from the infected area for study under a microscope.
For mild jock itch, your doctor may suggest first using an over-the-counter antifungal ointment, lotion, powder or spray. Apply the medication as your doctor recommends for one to two weeks even if the rash clears up quickly.
If you also have athlete's foot, it's usually treated at the same time as jock itch to reduce the risk of the rash coming back. Severe jock itch or a rash that doesn't improve with over-the-counter medicine may need prescription-strength creams, ointments or pills.
Your family doctor or a skin specialist (dermatologist) can diagnose jock itch. Here are some tips to help you get ready for your appointment.
Your time with your doctor may be limited, so preparing a list of questions can help you make the most of your appointment. For jock itch, some basic questions to ask your doctor include:
Your doctor is likely to ask you a number of questions, such as:
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