Jock itch (tinea cruris)

What is it?

The term "jock itch" typically describes an itchy rash in the groin. Although there are many causes of jock itch, this term has become synonymous with tinea cruris, a common fungal infection that affects the groin and inner thighs. Tinea is the name of the fungus; cruris comes from the Latin word for leg.

Jock itch can develop when tight garments trap moisture and heat. This creates an environment in which fungi multiply and flourish. Athletes often get jock itch. It occurs more commonly in men, but can affect women as well. The jock itch fungus may cause a rash on the upper and inner thighs, the armpits, and the area just underneath the breasts. Many people with tinea cruris also have athlete's foot. Athlete's foot is called tinea pedis.

Symptoms

A flat, red, itchy rash first appears high on the inner side of one or both thighs. It spreads outward in a ringlike circular pattern while the center clears up partially. The border is sharply marked, slightly raised and often beefy red in color. Jock itch can spread to the pubic and genital regions and sometimes to the buttocks.

Diagnosis

Your doctor often can make the diagnosis just by looking at the rash. Your doctor may gently scrape the skin to get a sample to look for fungi under the microscope. With stubborn cases, your doctor may send the sample to a laboratory to pinpoint the fungus that's causing the trouble. Other causes of a rash in the groin include yeast infection of the skin, seborrheic dermatitis and psoriasis.

Expected duration

Jock itch usually can be treated within weeks, although it commonly comes back. Treatment for chronic (long-lasting) infections may last one or two months.

Prevention

The healthier you are, the less likely you are to get conditions such as diabetes that increase the risk of a fungal infection. Remaining healthy through diet, rest and exercise is the first step in avoiding fungal infection.

Here are other steps you can take to remain fungus-free:

• Keep your body clean.
• Dry yourself well after showers and baths.
• Shower immediately after athletic activities.
• Wear loose clothing whenever possible.
• Do not share clothing or towels with others; wash towels frequently.
• Clean exercise equipment before use.
• Wear sandals in the shower area at the gym and swimming pool.

Treatment

Most likely, your doctor will prescribe a topical antifungal treatment for you to apply once or twice a day for at least two weeks. If you have athlete's foot, your doctor should treat that as well. Untreated athlete's foot can cause jock itch to return.

Because jock itch commonly comes back, you need to be extra cautious. You can apply powder daily to help keep the area dry. The itching can be alleviated with an over-the-counter treatment such as Sarna lotion. You also should avoid hot baths and tight-fitting clothing. Men should wear boxer shorts rather than briefs.

When to call a professional

Call your doctor whenever you develop a skin rash.

Prognosis

Treatment for jock itch is quick and usually effective, but the condition often comes back. The following people should be especially vigilant to prevent the problem from returning:

• athletes
• people with fungal infections that affect other parts of the body (such as athlete's foot)
• people who wear tight clothing
• people with damaged or altered immune systems.

Additional info

National Institute of Arthritis and Musculoskeletal and Skin Diseases
 https://www.niams.nih.gov/