Balanitis is an infection or inflammation of the skin on the head (glans) of the penis. In men who are not circumcised, this area is covered by a flap of skin known as the foreskin, or prepuce. Balanitis can occur in both circumcised and uncircumcised men, although it occurs more commonly in men who are not circumcised. Young boys generally are affected only if they have a very tight foreskin that is difficult to pull back.

A variety of infections and skin conditions can cause balanitis. These include:

Infections with yeast (Candida) or bacteria that live on the skin (the most common cause)

Sexually transmitted infections, such as herpes simplex

Irritation of the skin by soap, detergents or spermicidal jelly

Benign (noncancerous) skin conditions such as psoriasis

Some types of skin cancer (very rare)

While any man can develop balanitis, the condition is most likely to occur in men who have a tight foreskin that is difficult to pull back, or who have poor hygiene. Diabetes can make balanitis more likely, especially if the blood sugar is poorly controlled. High blood sugar causes elevated amounts of sugar in the urine. Sugar-rich urine that dribbles on to the glans and under the foreskin provides a friendly environment for yeast and bacteria. Also, people with poorly controlled diabetes have a harder time fighting infections.

When balanitis keeps recurring, it may be caused by a yeast infection transmitted back and forth between partners during sexual contact.