Xiaflex (collagenase from Clostridium histolyticum) is an injectable medication used to treat Peyronie’s Disease, or penile curvature.

Xiaflex is designed to be injected into the collagen scar tissue in the penis and dissolve it. The medication is FDA-approved for men with stable curvature between 30 and 90 degrees, and is not approved for men with complex deformities, calcified scar, or scar on the underside of the penis. Xiaflex involves up to 8 injections over 18 weeks (the injections are performed over 4 cycles that are 6 weeks apart and each cycle includes two injections that are about 2 days apart) and requires the patient to participate in penile stretching at home.

When to ask a Urologist about Xiaflex

You should speak with a Urologist about Xiaflex injections if you are bothered by a curve to your penis that has not changed for at least three months.


Typically covered by most insurances (although coinsurance and deductibles may apply). Coverage will be verified prior to proceeding. If you do not have insurance, our office will be able to give you an out-of-pocket cost estimate.


Randomized trials have demonstrated a 30% curvature improvement with average curve reduction by 18 degrees after four cycles of two injections each over 18 weeks.

Possible Side Effects

About 80% of patients have significant penile bruising and swelling following injection and 1% of patients experienced penile fracture or serious disruption of the erectile cylinder. Sexual activity must be avoided for 4 weeks following each injection to limit the risk of penile fracture.

Alternative Approaches

Alternatives to Xiaflex include observation without treatment, penile modeling with vacuum erection devices or traction devices, penile plication surgery, plaque incision and grafting surgery, and penile prosthesis surgery.

What to do to Prepare for Procedure

Before the first injection, you will have an erection medically induced in the office to carefully mark and measure the point of maximal curvature to ensure that the subsequent Xiaflex injections are administered to the appropriate location. In general, you should temporarily stop both blood-thinning medications prior to procedure.

What to Expect after Procedure

Most men experience significant bruising and swelling of the penis following each injection. Blisters and small blood pockets are also relatively common following injection.