Jock itch

Jock itch is a common fungal skin infection that may affect the skin of your genitals, inner thighs and buttocks. The infection is characterized by an itchy, red, often ring-shaped rash in these warm, moist areas of your body.

Also called tinea cruris, jock itch is closely related to other skin conditions with similar names. Tinea refers to a type of fungus, and cruris is the Latin word for "leg." Other common tinea skin infections include:

Jock itch gets its name from being most common in male athletes, but anyone can get the infection. It also can occur in people who are overweight or sweat a lot.

Although uncomfortable and bothersome, jock itch usually isn't serious, except possibly for people with weak immune systems. Treatment usually consists of keeping your groin area clean and dry and applying topical antifungal medications.

The signs and symptoms of jock itch may include:

Jock itch can make wearing underwear or tight clothing uncomfortable. Walking or exercising may aggravate the rash and worsen your signs and symptoms.

Fungal infections, such as jock itch, are caused by microorganisms that become parasites on your body. These mold-like fungi (dermatophytes) live on cells in the outer layer of your skin. Jock itch occurs when the skin cells in your groin area become too warm and moist, allowing a fungal infection to begin.

Jock itch is only mildly contagious. It can spread by sharing towels or clothing with someone who has the infection, or through direct contact or sexual intercourse.

The organisms that cause jock itch thrive in damp, close environments. Warm, humid settings that promote heavy sweating — thus washing away fungus-killing oils and making skin more prone to infection — also favor its spread. Jock itch often affects men who wear tight underwear or athletic supporters that aren't washed after each use. People who are obese or sweat a lot also are at higher risk of jock itch. Some people may be genetically prone to this type of infection.

Those at increased risk of jock itch include people with weakened immune systems, such as people with diabetes or HIV/AIDS. If you have atopic dermatitis — a chronic, inherited skin disease characterized by itchy, inflamed skin — you may be more susceptible to jock itch. The barrier in your skin that normally protects you from viral, bacterial and fungal infections often is weakened or compromised.

See your doctor if you have a rash on your skin that doesn't improve within two weeks. You may need prescription medication. If excessive redness, swelling, drainage or fever occurs, see your doctor.

Your doctor can determine if you have jock itch or another skin disorder, such as dermatitis or psoriasis. He or she will likely ask you about possible exposure to or contact with someone with jock itch.

Your doctor may take skin scrapings or samples from the infected area and view them under a microscope. If a sample shows fungi, treatment may include an antifungal medication. If the test is negative, but your doctor still suspects that you have jock itch, a sample may be sent to the laboratory to determine whether it will grow fungi under the right conditions. This test is known as a culture. Your doctor may also order a culture if your condition doesn't respond to treatment.

A fungal infection rarely spreads below the surface of the skin to cause serious illness. However, people with weak immune systems, such as those with diabetes or HIV/AIDS, may find it difficult to get rid of the infection.

For a mild case of jock itch, your doctor may advise you to apply an over-the-counter antifungal ointment, lotion, powder or spray. Most infections respond well to these topical agents, which include:

If jock itch is severe or doesn't respond to over-the-counter medicine, you may need a prescription-strength topical or oral medication. These include:

Topical

Oral

Side effects from oral medications include gastrointestinal upset, rash and abnormal liver functioning. Taking other medications, such as antacid therapies for ulcer disease or gastroesophageal reflux disease (GERD), may interfere with the absorption of these drugs. Oral medications for fungal infection may alter the effectiveness of warfarin, an anticoagulant drug that decreases the clotting ability of your blood.

Since the introduction of newer medicines, doctors rarely prescribe griseofulvin (Fulvicin, Grisactin), another oral medication, to treat fungal skin infections. It's effective, but can take longer to clear up the infection. Its most common side effect is headache, and it occasionally causes discomfort in the digestive tract, sensitivity to light, rashes or a drop in your white blood cell count. The most common use of griseofulvin is for people who are allergic to other antifungal medications, or for people who have other medical conditions that may be negatively affected, such as liver disease.

Reduce your risk of jock itch by taking these steps:

By Mayo Clinic staff