Jock itch (tinea cruris) is a fungal infection that affects the skin of your inner thighs, buttocks and genitals. Jock itch causes an itchy, red, often ring-shaped rash in these warm, moist areas of your body.
Jock itch gets its name because it is common in people who sweat a lot, as do athletes. It also often occurs in people who are overweight, but anyone — even women — can get this infection.
Although often uncomfortable and bothersome, jock itch usually isn't serious, except possibly for people with weak immune systems. Keeping your groin area clean and dry and applying topical antifungal medications are usually sufficient to treat jock itch.
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.
When to see a doctor
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.
Jock itch is caused by fungi called dermatophytes. These microscopic organisms are normal inhabitants of your skin, and their growth stays in check as long as your skin is clean and dry. But on some areas of the body where skin is likely to be moist and warm, such as the groin, the fungi grow and thrive, resulting in a fungal infection.
This infection is often caused by the same type of fungus that causes athlete's foot and sometimes ringworm of the scalp. In fact, the fungus that infects your groin area may be spread there from your own athlete's foot infection.
Jock itch can spread from person to person by shared use of contaminated towels or clothing or through direct contact during sexual intercourse with someone who has the infection.
The organisms that cause jock itch thrive in damp, close environments. Warm, humid settings that promote heavy sweating — thus washing away fungus-killing oils, making the skin more permeable and in turn making the skin more prone to infection — favor its spread. Jock itch often affects more men than women. Men wearing tight underwear or athletic supporters that aren't washed after each use might help explain this gender difference. People who are obese or sweat a lot also are at higher risk of jock itch.
People with impaired immune systems — such as people with diabetes or HIV/AIDS — also may be at increased risk of jock itch. If you have atopic dermatitis — a chronic, inherited skin disease characterized by itchy, inflamed skin — you may be more susceptible to jock itch. The barriers in your skin that normally protect you from viral, bacterial and fungal infections often are weakened or compromised.
Your doctor can determine if you have jock itch or another skin disorder, such as a dermatitis or psoriasis.
Your doctor may take skin scrapings or samples from the infected area and view them under a microscope. This is called a potassium hydroxide (KOH) test. 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 a lab 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.
For a mild case of jock itch, your doctor may suggest first using an over-the-counter antifungal ointment, lotion, powder or spray. Jock itch is treated with one of two types of antifungal medications — azoles or allylamines. Generally, allylamines require a shorter treatment time, while azoles are less expensive but require longer treatment time.
Most infections respond well to these over-the-counter and prescription topical agents:
Allylamines
Azoles
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
If you also have athlete's foot, treat it at the same time you are treating your jock itch so that both infections aren't likely to recur.
Side effects from oral medications include gastrointestinal upset, rash and abnormal liver function. 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.
Another oral medication, griseofulvin (GrifulvinV), is sometimes used to treat fungal skin infections. Although it's effective, it may take longer to clear up the infection. Potential side effects include headache, discomfort in the digestive tract, sensitivity to light, rashes or a drop in your white blood cell count. Griseofulvin may be used for people who are allergic to other antifungal medications, or for people who have other medical conditions that may be negatively affected by other medications, such as people with liver disease.
People with weak immune systems, such as those with diabetes or HIV/AIDS, may find it more difficult to get rid of this infection.
Reduce your risk of jock itch by taking these steps:
