Jock itch: causes, symptoms and treatment

Medical disclaimer: This page is general health information for education only. It is not medical advice and is not a substitute for diagnosis or treatment by a qualified health professional. It has not been reviewed by a clinician. In an emergency, call 911 or your local emergency number.

Jock itch is a common fungal skin infection of the groin. It causes an itchy, red, scaly rash, usually in the creases of the upper thighs. This page explains what causes jock itch, what it looks like, how clinicians diagnose and treat it, and how people lower their risk. It is general information for adults and teens, and it is not a way to diagnose a rash on your own.

What is jock itch?

Jock itch is a fungal infection of the groin area, known in medical terms as tinea cruris or ringworm of the groin.

MedlinePlus defines jock itch as an infection of the groin area caused by a fungus. The CDC groups it with other forms of ringworm, and notes that ringworm on the groin is often called jock itch. Despite the name, ringworm is caused by fungi, not by a worm.

The fungi behind these infections are called dermatophytes. These fungi affect the outer layer of the skin and hair. Jock itch sits in the same family as athlete’s foot, which is ringworm of the feet. You can find related skin and infection topics in our guide to common health conditions.

This page does not cover every rash in the groin. Other conditions, such as yeast infections and psoriasis, can look similar and need a clinician to tell them apart.

Jock itch symptoms

Jock itch usually causes an itchy, red, scaly rash in the skin folds of the inner thighs.

Signs described by MedlinePlus and the CDC include:

• Itchy, scaly, red spots, usually on the inner skin folds of the thigh.
• Red, raised, scaly patches that may blister and ooze.
• Patches with sharply defined edges and scale along those edges.
• Skin that turns darker or lighter than usual, sometimes permanently.
• A rash that may spread near the anus and cause itching there.

According to the CDC, symptoms typically appear 4 to 14 days after skin contact with the fungi. Ringworm rashes often look red on light skin and gray or brown on darker skin. Cleveland Clinic adds that jock itch can sting or burn as well as itch.

Jock itch usually stays around the upper thigh creases. MedlinePlus notes that it does not usually involve the scrotum or penis. A rash that mainly affects the genitals may have another cause, and this page does not describe those conditions.

What causes jock itch and who gets it

Jock itch happens when fungi that thrive in warm, moist skin grow and spread in the groin.

Known triggers and ways it spreads include:

• Friction from clothing and long periods of moist skin, such as from sweating.
• Direct skin-to-skin contact with someone who has the infection.
• Contact with unwashed clothing or shared towels.
• Spread from athlete’s foot, for example when a waistband touches infected feet.

MedlinePlus reports that jock itch occurs mostly in adult men and teenage boys. It is also more common in people who are overweight and have deep, moist skin folds. A review hosted by the National Library of Medicine lists heavy sweating, tight clothing, diabetes and a weakened immune system as risk factors. Our page on diabetes symptoms and care explains that condition in more depth.

The CDC notes that people with weakened immune systems may be especially at risk for ringworm. Learn more about how your immune system protects the body. These risk factors raise the chance of infection. They do not mean a person will get jock itch.

How jock itch is diagnosed

Clinicians can usually diagnose jock itch by looking at the skin, and extra tests are often not needed.

When tests are needed, MedlinePlus lists these options:

• A KOH exam, a simple office test that uses a potassium hydroxide solution to check a skin sample for fungus.
• A skin culture of a sample taken from the rash.
• A skin biopsy with a special stain to identify fungus and yeast.

The CDC recommends that clinicians test for suspected ringworm to choose the best treatment. It warns that misdiagnosis and delayed treatment allow symptoms to progress.

Testing matters because other conditions look alike. The NLM review names candidiasis, erythrasma, psoriasis and seborrheic dermatitis as conditions with signs similar to jock itch. Each of these is a separate skin condition that can affect the groin. This page cannot help you tell these conditions apart at home.

How clinicians treat jock itch

Jock itch is treated with antifungal medicines, most often creams or powders applied to the skin.

The CDC states that jock itch is usually treated with non-prescription antifungal medications. These are applied to the skin, usually for 2 to 4 weeks. The NLM review lists two main classes of skin treatments, called azoles and allylamines.

When the infection lasts longer than 2 weeks, is severe or keeps coming back, a clinician may prescribe:

• Stronger antifungal medicines applied to the skin.
• Antifungal medicines taken by mouth, which the NLM review reserves for chronic, recurrent or hard-to-treat cases.
• Antibiotics if scratching leads to a bacterial skin infection.

The CDC advises against steroid creams for ringworm or for any rash that has not been diagnosed. Steroids can make ringworm worse. Cleveland Clinic stresses finishing the full course of medicine, because stopping early can let jock itch come back.

This page does not recommend any product, dose or treatment plan. Your clinician chooses treatment based on your exam and your health history.

How to lower your risk

Keeping the groin clean and dry is one of the key steps sources list for lowering your risk of jock itch.

Prevention steps from the CDC and MedlinePlus include:

• Keep your skin clean and dry, especially after sweating or bathing.
• Change socks and underwear every day.
• Wear loose-fitting underwear and avoid clothing that rubs the groin.
• Wash athletic supporters and workout clothes often.
• Do not share towels, sports gear or other personal items.
• Wear protective footwear in public showers and locker rooms.

Because athlete’s foot can spread to the groin, getting it checked and treated also helps. These steps lower risk, but they do not guarantee you will avoid infection.

When to see a clinician

See a clinician if a groin rash does not improve within about 2 weeks, gets worse, or comes with pain or fever.

MedlinePlus advises contacting your provider if jock itch does not respond to home care after 2 weeks. Mayo Clinic advises seeing a doctor if the rash is painful or you develop a fever. Cleveland Clinic adds a rash that looks infected, with swelling, or one that spreads to other parts of the body.

Tell your clinician if you have diabetes or a weakened immune system, because both are listed risk factors. If you are unsure whether a rash needs attention, our page on how to prepare for an appointment can help you plan the visit. This section does not cover rashes in young children, who should be seen by their own clinician.

Questions to bring to your appointment

These questions can help you get clear answers during your visit. They do not replace your clinician’s advice about your own situation.

• Is this rash jock itch, or could it be another condition?
• Do I need a test such as a KOH exam or skin culture?
• How long should treatment last, and what should I expect as it works?
• Could I also have athlete’s foot, and should that be treated too?
• What signs mean I should come back sooner?
• What can I do to keep jock itch from coming back?