Jock Itch

Jock itch is the common term for a fungal infection called tinea cruris.  It usually manifests itself as intense itching, redness, and scaling skin of the groin that often involves the upper thighs, the scrotum, the area behind the scrotum, and even up into the crack of the buttocks towards the anus.  Basically any area covered by pubic or other body hair in the groin can be affected.  Rarely does the penis become affected (if it does, it’s usually on the very base of the penis where there is some thicker pubic hair).


Fungus likes to grow in warm, dark, moist areas and spreads in areas where skin touches skin.  This makes the male genitals a prime target for fungal growth since it is warm, dark, and there are many surfaces where skin touches skin.  The skin of the scrotum lying against the skin of the upper thigh, as well as the penis lying on top of the scrotum presents plenty of places for fungus to grow.  In addition, the groin is often moist due to sweating (the groin area is the “armpit” of the legs and has many of the same types of sweat glands as the armpits).  Most men notice that after working out their groin area is damp or wet with sweat.  These factors all increase the likelihood of a fungal infection.

How does fungus reach the groin?  The majority of jock itch cases are caused by fungus being transferred to the groin from the feet.  Most men know what athlete’s foot is, or have experienced it at some time.  Athlete’s foot is the same fungus as jock itch.  Like jock itch, athlete’s foot causes intense redness and itching in between the toes and on the lower portions of the foot.  Since athlete’s foot and jock itch are caused by the same fungus, the fungi can be transferred easily from the foot to the groin via the underwear.  This occurs when a man is putting on his underwear.  His feet brush the groin area of the underwear as he puts his foot into the leg holes.  This brushing of the foot against the underwear can leave fungus on the underwear, which then sits next to the warm, moist, dark areas of the groin to grow and spread.  Because of this, it is important to avoid athlete’s foot and to prevent transmission of fungus from the foot to the groin.  Men with athlete’s foot can prevent jock itch by putting socks on their feet before putting on their underwear.


Dirty, and especially shared, shower spaces are ripe areas for fungus to grow.  The term athlete’s foot comes from the fact that men who shower in common areas like the gym are at higher risk of developing athlete’s foot.  In these areas men should consider wearing rubber flip flops or slip-on shoes to prevent the feet from touching the shower floor.  At home, cleaning the bottom of the shower area with hot, soapy water when someone does have athlete’s foot can prevent the fungus from spreading to others.  


Drying after a shower can also allow fungus to pass from the foot to the towel, then to the groin.  This can occur when a man dries a foot infected with athlete’s foot then dries his genitals with the same towel.  When a man has any type of fungal infection, it’s a great idea to dry the affected area (foot or groin) with a dry washcloth that is ONLY used to dry that area and no other areas.  Use a clean, dry washcloth for each shower/bath.  In addition, fungal infections can be spread through laundry.  Once someone in the household has an infection, others can get it too or it can spread to other parts of the body.  Socks of men that have athlete’s foot and underwear of men that have jock itch (as well as their drying cloth/towel) should be washed separately from other clothing in HOT water to kill the fungus and prevent spreading it from one article of clothing to another. 

In addition, completely drying the affected area(s) is important.  One reason jock itch occurs frequently is that men sweat in their groin.  Also, the groin is one of the least “well-dried” areas after taking a shower.  This area rarely “air dries” as most men put on their underwear almost immediately after getting out of the shower.  Once a man has jock itch, it’s important to keep the area very dry.  We’ve already discussed using a separate dry washcloth or towel to dry the affected area, but further air drying is also a good idea.  This may include waiting a couple of minutes after drying off from a shower before putting on underwear to allow the area to air dry.  Another option that works well to completely dry the area may seem a little strange-- blow drying the groin area with a hair dryer can evaporate any remaining moisture that may be trapped in all the skin folds and tight areas of the groin.  Just be sure the temperature of the hair dryer is set to “no heat” to prevent overheating the testicles or burning the skin.  Wearing boxers rather than tighter fitting briefs can also allow more airflow.


Once these steps have been taken to prevent the spread of jock itch, applying an antifungal medication can help kill the fungus.  Multiple products are available over-the-counter.  The main products available over-the-counter are terbinanfine, clotrimazole, and miconazole creams.  Terbinafine tends to work better and only needs to be applied once a day (the other two medications have to be applied twice a day).  Most OTC jock itch products come as creams.  Although creams are highly effective, they’re sometimes difficult to apply, especially in areas where the infection has spread into the thicker pubic hair or onto the scrotum.  If the infection has spread to areas well covered by hair, ensure that the cream reaches the skin surface.  In some cases, you may need to get a prescription for an antifungal shampoo if the area affected is well covered by hair and not responding to over-the-counter creams.  If the infection has spread onto the scrotum, ensure the cream gets into all the folds and wrinkles.  Miconazole comes in an aerosol powder.  This can be sprayed onto the genitals and may be easier to “apply” than cream.  Follow the package directions that come with any over-the-counter products to ensure you’re using them correctly and as often as you should.  If an infection hasn’t gone away in a week or is severe, stronger products can be prescribed by your healthcare provider.

Treating an infection with antifungals and taking the measures above to keep the area dry and prevent transmission or reinfection due to infected clothing/towels can go a long way to shorten how long jock itch lasts.

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  1. Timonina/