Cases of Peyronie's disease range from mild to severe. Symptoms may develop slowly or appear overnight. In severe cases, the hardened plaque reduces flexibility, causing pain and forcing the penis to bend or arc during erection. In many cases, the pain decreases over time, but the bend in the penis may remain a problem, making sexual intercourse difficult. The sexual problems that result can disrupt a couple's physical and emotional relationship and lead to lowered self-esteem in the man. In a small percentage of patients with the milder form of the disease, inflammation may resolve without causing significant pain or permanent bending.

The plaque itself is benign, or noncancerous. A plaque on the top of the shaft (most common) causes the penis to bend upward; a plaque on the underside causes it to bend downward. In some cases, the plaque develops on both top and bottom, leading to indentation and shortening of the penis. At times, pain, bending, and emotional distress prohibit sexual intercourse.

One study found Peyronie's disease in 1 percent of men. Although the disease occurs mostly in middle age, younger and older men can develop it. About 30 percent of men with Peyronie's disease develop fibrosis (hardened cells) in other elastic tissues of the body, such as on the hand or foot. A common example is a condition known as Dupuytren's contracture of the hand. In some cases, men who are related by blood tend to develop Peyronie's disease, which suggests that genetic factors might make a man vulnerable to the disease.

Men with Peyronie's disease usually seek medical attention because of painful erections and difficulty with intercourse. Since the cause of the disease and its development are not well understood, doctors treat the disease empirically; that is, they prescribe and continue methods that seem to help. The goal of therapy is to keep the Peyronie's patient sexually active. Providing education about the disease and its course often is all that is required. No strong evidence shows that any treatment other than surgery is effective. Experts usually recommend surgery only in long-term cases in which the disease is stabilized and the deformity prevents intercourse.

Because the course of Peyronie's disease is different in each patient and because some patients experience improvement without treatment, medical experts suggest waiting 1 to 2 years or longer before attempting to correct it surgically. During that wait, patients often are willing to undergo treatments whose effectiveness has not been proven.

Some researchers have given vitamin E orally to men with Peyronie's disease in small-scale studies and have reported improvements. Yet, no controlled studies have established the effectiveness of vitamin E therapy. Similar inconclusive success has been attributed to oral application of para-aminobenzoate, a substance belonging to the family of B-complex molecules.

Researchers have injected chemical agents such as verapamil, collagenase, steroids, and calcium channel blockers directly into the plaques. These interventions are still considered unproven because studies included small numbers of patients and lacked adequate control groups. Steroids, such as cortisone, have produced unwanted side effects, such as the atrophy or death of healthy tissues. Another intervention involves iontophoresis, the use of a painless current of electricity to deliver verapamil or some other agent under the skin into the plaque.

Radiation therapy, in which high-energy rays are aimed at the plaque, has also been used. Like some of the chemical treatments, radiation appears to reduce pain, but it has no effect at all on the plaque itself and can cause unwelcome side effects. Although the variety of agents and methods used points to the lack of a proven treatment, new insights into the wound healing process may one day yield more effective therapies.

Peyronie's disease has been treated surgically with some success. The two most common surgical procedures are removal or expansion of the plaque followed by placement of a patch of skin or artificial material, and removal or pinching of tissue from the side of the penis opposite the plaque, which cancels out the bending effect. The first method can involve partial loss of erectile function, especially rigidity. The second method, known as the Nesbit procedure, causes a shortening of the erect penis.

Some men choose to receive an implanted device that increases rigidity of the penis. In some cases, an implant alone will straighten the penis adequately. In other cases, implantation is combined with a technique of incisions and grafting or plication (pinching or folding the skin) if the implant alone does not straighten the penis.