What is jock itch?
Jock itch (tinea cruris) is a form of ringworm. Ringworm is not a worm at all. It is a fungal infection of the outer layers of skin, hair, or nails. Fungi (plural of fungus) are present everywhere in our environment.
Ringworm of the skin appears as a rash with patches that may be red or peeling or that have bumps on the edges that look like blisters. The skin often is itchy, and the rash can spread quickly. You can have both jock itch and athlete's foot (tinea pedis) at the same time.
What causes jock itch?
Jock itch is caused by a fungus. Fungi commonly grow on or in the top layer of skin. They may or may not cause an infection. Fungi grow best in warm, moist areas of the body such as the groin, inner thighs, and buttocks.
As the name suggests, jock itch mostly affects male athletes, but anyone can get it. Using public showers and locker rooms increases your chances of getting jock itch. Fungi grow best in the steamy rooms among damp towels, sweaty workout clothes, and wet floors. So it's not surprising that jock itch and athlete's foot often occur at the same time, since both are caused by fungi.
What are the symptoms of jock itch?
Symptoms of jock itch include the following:
- Itching and pain are common.
- A rash is on the groin, skin folds, inner thighs, or buttocks. The rash usually does not occur on the scrotum or penis.
- The edge of the rash is very distinct and may be scaly or have bumps that look like blisters.
- The centre of the rash may have a red-brown colour.
How is jock itch diagnosed?
Jock itch is annoying, but it usually is not serious. If you have had jock itch in the past, you may recognize the symptoms. Your doctor can tell if you have jock itch after asking questions about your symptoms and past health and by looking at your rash. Your doctor may scrape a little of the rash on a glass slide so that he or she can look at it under a microscope.
How is jock itch treated?
Most ringworm infections of the skin, such as jock itch, can be treated at home with antifungal creams and powders you can buy without a prescription. But have your doctor look at any infection that does not go away, is severe, or comes back. To treat jock itch, follow these steps:
- Wash the rash with soap and water. Spread an antifungal cream over the rash. Apply the cream beyond the edge of the rash.
- Use an antifungal cream or powder that contains terbinafine, miconazole, clotrimazole, or naftifine. You can buy these products without a prescription. Brand names include Lamisil, Naftin, Canesten, Monistat-Derm, and Micatin. Follow the directions on the package, and don't stop using the medicine just because your symptoms go away. Use the medicine exactly as the label says. If symptoms do not improve after 2 weeks, call your doctor.
- In rare cases, ringworm of the skin causes large areas of blisters. If your ringworm forms blisters, you can use compresses (such as Burow's compress, which you can buy without a prescription) to soothe and dry out the blisters. After the skin is dried out, use antifungal creams that you can buy without a prescription.
- If you have jock itch and athlete's foot, you should treat both to prevent reinfecting your groin when you put on your underwear.
How can I prevent jock itch?
You can help prevent jock itch by keeping your groin, inner thighs, and buttocks clean and dry. Dry off well after you exercise and shower. Try these other steps to prevent jock itch:
- Wash your workout clothes, underwear, socks, and towels after each use.
- Wear shower shoes when you use public showers and locker rooms.
- If you have athlete's foot, you should treat it. During treatment, put your socks on before you put on your underwear. This will prevent the spread of the fungus from your feet to your groin.
- If you keep getting athlete's foot, dry your feet last when you towel off after a shower or bath. This can help prevent spreading infection from your feet to your groin.
Other Works Consulted
- Schieke SM, Garg A (2012). Superficial fungal infection. In LA Goldman et al., eds., Fitzpatrick's Dermatology in General Medicine, 8th ed., vol. 2, pp. 2277–2301. New York: McGraw-Hill.
Current as of: October 31, 2019
Author: Healthwise Staff
Medical Review: William H. Blahd, Jr., MD, FACEP - Emergency Medicine
Adam Husney, MD - Family Medicine
Martin J. Gabica, MD - Family Medicine
Kathleen Romito, MD - Family Medicine
David Messenger, BSc, MD, FRCPC, FCCP - Emergency Medicine, Critical Care Medicine
Current as of: October 31, 2019