When a man has Peyronie’s disease, there is scar tissue inside of the penis that causes it to excessively curve. This abnormal curvature is usually more noticeable and/or painful when the penis is erect. If the curvature is severe, it can contribute to erectile dysfunction (ED) and other issues that may cause emotional and physical problems for men.

Some patients see improvements with a blood pressure medication called verapamil and a type of protein known as interferon. But the only FDA-approved medication specifically for Peyronie’s disease is XIAFLEX®.



XIAFLEX® (collagenase clostridium histolyticum) is a medication normally administered as a series of injections. It’s meant for use on men with severe curvatures of the penis with a noticeable nodule. Specifically, it corrects scaring caused by a build-up of collagen, which is found in the plaques in the penises of men with Peyronie’s disease.

How Does It Work?

Injections of XIAFLEX® work by breaking down the excess collagen that causes one side of the penis to bend excessively in the opposite direction. It gradually breaks down this substance. As collagen is broken down, affected tissues in the penis regain their natural elasticity. When a man has an erection following successful treatment, his penis should be able to expand with a bend that’s not as severe or disruptive to normal functions.

How Is XIAFLEX® Administered?

XIAFLEX® is administered as an injection by a urologist during an office visit. The medication is injected into plaque in the penis. A local anesthetic is sometimes used when the injection is given to ease discomfort. The injection process is broken down into “treatment cycles.” Each cycle consists of two injections of XIAFLEX®. The second injection is usually given a few days after the first one is administered.

How Many Treatment Cycles Are Needed?

There is no standard number of treatment cycles. The recommended amount of cycles will depend on factors such as the extent of the curvature and how well tissues in the affected area of the penis respond to the injected medication. Treatment cycles are typically spaced about 4-6 weeks apart. Some men may see improvements after one or two cycles, while men with severe curvatures may benefit more from three or four cycles.

What Happens Between Injections and Cycles?

Men are usually instructed not to have intercourse between the first and second injections during a treatment cycle. As far as activity between cycles, men are typically advised not to have sex for at least two weeks after a cycle has been completed, or until given the okay by the urologist who is providing treatment. Patients are normally instructed to perform straightening and stretching exercises to help restore the normal curvature of the penis. Patients should inform their doctor if any pain is experienced when performing the recommended exercises.

Possible Side Effects

Possible side effects associated with XIAFLEX® may include bruising, redness, swelling, pain, and itching. Most patients using this medication do not experience serious side effects. In order to avoid possible issues with injections, men should inform their urologist if they have allergies or bleeding or clotting problems.

Injections of XIAFLEX® may be more effective if they are combined with a technique referred to as modeling. If the deformity is severe and XIAFLEX® injections aren’t effective, surgery involving suturing of the unaffected side or incisions and grafting may be performed. Penile implants may become an option if Peyronie’s disease is combined with erectile dysfunction and medication isn’t effective.