Rash on the glans penis, which is subjective almost not worried man, often indicates a mild inflammatory or allergic process. For moderate and severe rashes capture a large area of the mucosa, tend to merge and can disrupt the general condition of the men. A painful rash and redness on the underside of your penis or the head of your penis can signal a yeast infection. Yeast is a common fungus , but when it grows too much, it can cause problems. Red penis rash is common to occur during someones lifetime and varies with age and setting, it can be many things. Balanitis is one of the most common, and is a natural infection under the foreskin, which is the most common reason for a red penis. balanitis is an inflammation of the tip, or glans, of the penis. Symptoms of balanitis include inflammation of the glans a rash, which appears as blotchy red or purple patches on the glans or. a penis rash can be identified when there are spots of irritated or swollen skin on the penis. The rash may also be present in the groin area or other parts of the genitals. the infection of human papillomavirus can increase the chances of getting penis cancer. Syphilis is a known sexually transmitted disease that can result in red std rash on genital organ and other skin parts. This infection can affect foreskin, glans, penile shaft and scrotum to develop red or pink fluid-filled blisters or bumps. to soothe the rash, you can use steroid creams or ointments. Balanitis is a common infection of the penis tip and foreskin. It causes rash, redness, itching, swelling, pain and discharge in the affected area. An unusual rash, bump, or growth on your penis may have infectious and non-infectious causes, including allergy and sexually transmitted diseases. Lichen planus is a rare skin condition characterized by raised, flat, violet-colored bumps on the glans of the penis. The bumps sometimes have fine white streaks and a smooth surface. A rash on penis, penile shaft, head or glans can be a sign of an std, irritation or even allergic reaction. Itchy penile rashes can occur on different parts, including the base, on the scrotum, shaft or head.