Causes of Peyronie's Disease

Medically Reviewed by Sabrina Felson, MD on November 07, 2022
2 min read

In Peyronie's disease, scar tissue makes the penis bend or curve during an erection.

When a guy gets an erection, chambers on the side of the penis fill with blood. There’s a stretchy sheath that covers the chambers so it can grow. But with Peyronie’s, scar tissue (also called plaque) on the sheath keeps your penis from standing straight. The scar tissue can stop a chamber from fully filling up, which forces the penis to bend.

If the scar forms on the top of the penis -- which is what usually happens -- the penis curves up. If it forms on the bottom of the penis, it curves down. Scar tissue can also form on both the top and bottom, making the penis shorter and dented.

No one knows for sure what causes Peyronie's disease. Many doctors think the scarring might be caused by a minor injury to the penis during sex -- from accidental bending, for example. But lots of men with the condition don't remember that type of injury.

Older men, whose erections tend to bend more easily, are more likely to get Peyronie’s than younger men. Genetics may also play a part.

Men who have Peyronie’s disease are more likely to also have Dupuytren’s contracture. That’s where tissue in the hand becomes scarred and thickened. It can force fingers to curl in toward your palm.

You may notice a hard lump just below the skin of your penis right around where the curve starts. Sometimes, though, the scar tissue is too deep to feel.

Scar tissue can vary in size from small to large and isn't always in just one spot. Sometimes the scar tissue goes around the penis, causing it to shorten. That can cause problems with erections, but no curving.

In addition to a curve, other symptoms may include a lack of firmness, which may make it hard to keep an erection. Your doctor may suggest treatment for a curve of 30 degrees or more, especially if you have problems having sex.

Even before you notice a curve, you may have painful erections. The pain comes from inflammation caused by the injury and can last for many months. The pain usually eases once the injury heals and the scar tissue hardens.

Doctors typically diagnose Peyronie’s disease by asking about symptoms and any injuries, and by examining the penis. Some doctors inject drugs into the penis to cause an erection so they can see the angle. If you bring in a photo of your erection, you can probably skip this. Your doctor may also order an ultrasound test of the area.

There are ways to treat Peyronie’s. If you see a family doctor or internist for the problem, they may refer you to a urologist for treatment.