Xiaflex for Peyronie’s Disease: A Non-Surgical Way to Straighten Penile Curvature

最終更新日： 9月 3, 2026

Few conditions in men’s health carry as much quiet distress as ペイロニー病. A man notices that his penis has started to bend during erection. Intercourse becomes difficult or painful. Confidence drains away. And because the subject feels embarrassing, many men wait years before asking anyone about it — often assuming that surgery is the only way out.

It is not. In 2013, the United States Food and Drug Administration approved Xiaflex (collagenase clostridium histolyticum) as the first — and still the only — non-surgical treatment approved specifically for Peyronie’s disease. For the right patient, a course of injections can meaningfully reduce the curve without ever entering an operating theatre.

This article explains, in plain language, why the penis curves in the first place, how Xiaflex works, who qualifies, what results are realistic, and what risks men should know about before saying yes. If Xiaflex is something you are interested in, please email the Urology department at bhquro@bdms.co.th to enquire first.

Why the Penis Curves: Understanding Peyronie’s Disease

Inside the penis are two erectile chambers, wrapped in a strong but flexible sheath of connective tissue called the tunica albuginea. During an erection, blood fills the chambers and this sheath stretches evenly all the way around — which is what keeps the erection straight.

Peyronie’s disease is believed to start with small, often unnoticed injuries to that sheath — a bend or buckle during intercourse, for example. In most men these tiny injuries heal without a trace. But in men who are predisposed to the condition, likely for genetic reasons, the healing process goes wrong. Instead of settling down, the body lays down excess collagen and forms a dense, inelastic scar known as a plaque.

Here is the key idea: that plaque cannot stretch. When an erection occurs, the healthy tissue on one side expands normally while the scarred side stays rigid and short. The penis is pulled toward the scar — and that is the curve. The direction and severity of the bend simply reflect where the plaque sits and how large it is.

Peyronie’s disease most often appears in men around their early fifties, though it can occur earlier or later. Beyond the physical deformity, it commonly brings pain, difficulty with penetration, 勃起不全, a sense of shortening, and — very frequently — depression and strain on relationships. The emotional toll is not a footnote to this condition; for many men it is the main reason they finally seek help. If low mood is a large part of the picture, it deserves treatment in its own right alongside anything done for the curve.

How Xiaflex Works: Dissolving the Scar

If the problem is a collagen scar that will not stretch, the logical solution is to break down that collagen. That is exactly what Xiaflex does.

Xiaflex is a purified mixture of two enzymes called collagenases, produced by a bacterium. Think of them as molecular scissors that are specifically shaped to cut collagen. When injected directly into the plaque, the two enzymes work together to dismantle the exact types of collagen that make up Peyronie’s scar tissue.

What makes this useful rather than dangerous is its selectivity. At the doses used in treatment, laboratory studies show these enzymes break apart the fibrous collagen of the plaque without damaging the arteries, nerves, or large veins running through the penis. The scissors cut the scar and leave the wiring alone.

Research also suggests a second, quieter benefit: the enzyme appears to reduce the activity of the cells and signalling molecules that were driving the scarring in the first place. So it does not just cut existing scar — it may also help switch off the process that maintains it. That mechanism comes from laboratory work rather than from patient outcomes, so treat it as a plausible explanation rather than a proven additional benefit.

The injection alone is only half the treatment. A few days later, the doctor performs penile modeling — gently but firmly stretching and bending the penis away from the direction of the curve. Because the plaque has been chemically weakened, this manual stretching helps break the softened scar apart and restore elasticity to the sheath. Injection and modeling together are what produce the straightening.

Who Is a Candidate?

Xiaflex is not for every man with a bend. It is approved for adult men who meet specific criteria:

• A plaque the doctor can feel on examination — there must be a definite target to inject.
• A curve of at least 30 degrees at the start of treatment. Milder curves generally do not require this therapy.
• Stable disease — meaning the curve has stopped getting worse and the pain with erections has typically settled. Treating during the active, inflammatory phase is not appropriate.
• Intact erectile function, with or without the help of ED medication.

The American Urological Association guideline supports using this injection together with penile modeling for men with stable disease and a curve greater than 30 degrees but less than 90 degrees, provided erectile function is preserved. Very severe curves, hourglass-shaped narrowing with instability, or plaques that have hardened into bone are generally better addressed surgically.

One important detail: in the United States, Xiaflex is available only through a restricted safety programme, and only doctors who have completed specific training are permitted to administer it. That restriction exists because of the rare but serious risk of injury to the erectile chambers — which is precisely why the choice of provider matters as much as the choice of treatment.

What the Treatment Course Looks Like

Treatment is delivered in cycles rather than as a single shot. Each cycle looks like this:

1. Two injections into the plaque, given a few days apart.
2. Penile modeling by the doctor, performed a few days after the second injection.

A full course runs to a maximum of four cycles, spaced roughly six weeks apart — so the complete programme spans around six months. If the curve improves enough along the way, or if the doctor judges that further treatment is not warranted, the remaining cycles are simply not given.

Before each injection, the doctor induces an erection in the clinic in order to see exactly where the plaque is pulling and to mark the target. The penis is allowed to return to a resting state before the injection itself is given. This is a clinic procedure, not an operation — no general anaesthetic, no hospital admission.

What Results Can You Realistically Expect?

This is the part of the conversation I consider most important, because managed expectations are the difference between a satisfied patient and a disappointed one.

Xiaflex reduces the curve. It does not usually make the penis perfectly straight. Across the large clinical trials and real-world series, the typical man sees roughly a third of his curvature corrected. A severe bend becomes a manageable one. A manageable bend often becomes barely noticeable. But some residual curve after treatment is normal, not a failure.

Several other findings are worth knowing:

• Finishing the course matters. Response builds cycle by cycle. Many men who see little change after the first cycle go on to respond well by the end of the fourth — which is why stopping early out of impatience is one of the most common avoidable mistakes.
• Bother improves, not just geometry. Men consistently report meaningful improvement in how much the condition troubles them — often the outcome they actually care about.
• Many men avoid surgery altogether. In follow-up studies, a majority of treated men felt the therapy was worthwhile, and a substantial proportion said it removed their need for an operation and restored their ability to have intercourse.
• The benefit lasts. Men followed for five years after treatment kept their improvement — and on average continued to straighten slightly further over time, with no additional injections and no long-term safety concerns identified.

Outcomes tend to be better in men who start with a more pronounced curve, who complete more cycles, who have strong night-time erections, and who use a penile traction device alongside treatment as directed.

Are There Other Injection Options?

Xiaflex is the only injection approved specifically for Peyronie’s disease, but a few other agents are used off-label. Two points before the list: none of these is in routine use in this clinic, and off-label means the evidence and the regulatory approval do not extend to this condition.

• Interferon alpha-2b — the best-studied alternative. It works differently, by calming the scarring process rather than cutting collagen directly, and does produce measurable straightening. The guideline supports it as an option, though on weaker evidence than Xiaflex. Flu-like side effects such as fever, muscle aches, and fatigue can limit how well men tolerate it.
• Verapamil — a blood-pressure medication used off-label on the theory that it reduces scar formation. The evidence here is inconsistent, and comparative analyses place it behind both Xiaflex and interferon. It is not offered here.
• Other agents — hyaluronic acid, steroids, and botulinum toxin have all been tried, but the supporting studies are small and the evidence remains thin. These are not offered here either.

Put simply: Xiaflex has the strongest evidence and the only formal approval, interferon is a reasonable second choice, and the rest are best regarded as investigational.

Risks and Side Effects

Xiaflex is generally well tolerated, but it is a real medical procedure with real risks, and men deserve an honest account of them.

Common and expected

Most treated men experience at least one side effect, but the great majority are mild to moderate and settle on their own within about two weeks. The three you should expect to see are bruising of the penile skin, swelling around the injection site, and pain in the penis. These look alarming and feel uncomfortable, but they are the normal aftermath of the treatment doing its job.

Uncommon but serious

• Corporal rupture (penile fracture) — the most serious complication, and the reason for the restricted training programme. It is rare, but it happens. Most cases occur within about two weeks of injection and are triggered by intercourse or a spontaneous morning erection acting on a temporarily weakened sheath. Some cases need surgical repair; others can be managed without surgery.
• Severe bleeding into the penis (hematoma) — uncommon, but occasionally requires a procedure to resolve.
• Skin and soft-tissue damage — rare, reported as a consequence of severe hematoma.

Because Xiaflex is a bacterial protein, the body does form antibodies against it. Long-term follow-up has found no clinical consequence from this. And one reassuring point that comes up in almost every consultation: studies have いいえ found Xiaflex to cause penile shortening.

The One Rule Patients Must Follow

If you take away a single practical instruction from this article, make it this one.

From the first injection of a cycle through the modeling appointment, and for at least two weeks after modeling, you must abstain from intercourse and other sexual activity. The plaque has been deliberately weakened — that is the treatment working — and an erection under mechanical stress during this window is exactly how ruptures happen. This is not a cautious suggestion; it is the single most effective thing a patient can do to protect himself.

Go to an emergency department the same day if you experience a popping sound or sensation, sudden loss of an erection, severe pain, or marked swelling — this may be a corporal rupture, and it is repaired best when it is treated early rather than observed. In Thailand the emergency number is 1669. An erection lasting longer than four hours is also a urological emergency and should not wait for a clinic appointment.

結論

Peyronie’s disease was, for a long time, a condition where men were offered either watchful waiting or an operation. Xiaflex changed that. By enzymatically dissolving the collagen scar that causes the bend — and combining that with modeling to restore elasticity — it offers men with stable disease and a significant curve a genuine middle path.

It will not deliver a perfectly straight result, and it demands patience across a six-month course and strict discipline about activity restrictions. But for the right candidate, it meaningfully reduces the curve, eases the distress that comes with it, and in many cases removes the need for surgery altogether.

If your curve is severe, unstable, or accompanied by erectile dysfunction that medication cannot manage, surgery may still be the better answer. That decision belongs in a proper consultation, not on a website. See how ペイロニー病の治療 is structured in practice, including when penile prosthesis surgery becomes the more appropriate option.

If you have noticed a bend in your erection, pain, or difficulty with intercourse, please do not spend years hoping it resolves on its own. Dr. Soarawee Weerasopone offers specialist consultations in men’s health and Peyronie’s disease at バンコク病院本部 and at Samitivej Sriracha Hospital, Chonburi — 088-022-1445. If you are specifically interested in Xiaflex, please email the Urology department at bhquro@bdms.co.th to enquire first.

Bangkok Hospital Telemedicine is available for patients who cannot attend in person, including international patients — arrange it in advance by email to the Urology department at bhquro@bdms.co.th. Samitivej Sriracha is in-person only. For any enquiry about the cost of consultation or treatment, please contact the hospital directly at the same address, or Samitivej Sriracha on 088-022-1445.

Frequently Asked Questions About Xiaflex and Peyronie’s Disease

How do I enquire about Xiaflex?

By email. If Xiaflex is something you are interested in, write to the Urology department at bhquro@bdms.co.th and ask before making any plans around it.

Will Xiaflex make my penis completely straight?

Usually not completely. Xiaflex reliably reduces penile curvature — the typical man sees roughly a third of his curve corrected — but some residual bend after treatment is normal rather than a sign of failure. The realistic goal is to turn a curve that interferes with intercourse into one that does not. Men with more severe starting curves, those who complete all four treatment cycles, and those who use a penile traction device as directed tend to see the best results.

How does Xiaflex actually work?

Peyronie’s disease causes a collagen scar, called a plaque, to form in the sheath surrounding the erectile chambers. Because that scar cannot stretch during an erection, the penis bends toward it. Xiaflex contains enzymes that act like molecular scissors, cutting the collagen that makes up the scar while leaving arteries, nerves, and large veins undamaged. A penile modeling procedure performed by the doctor a few days later stretches the weakened plaque apart, restoring elasticity and reducing the curve.

Who qualifies for Xiaflex treatment?

Xiaflex is approved for adult men who have a plaque the doctor can feel on examination, a curve of at least 30 degrees, stable disease meaning the curvature has stopped worsening and erection pain has settled, and intact erectile function with or without medication. Guidelines support its use for curves greater than 30 degrees and less than 90 degrees. Very severe curves, unstable hourglass deformities, or calcified plaques are generally better treated surgically.

Is Xiaflex safe, and what are the main risks?

Most men experience bruising, swelling, and pain in the penis, which are expected and usually settle within about two weeks. The most serious risk is corporal rupture, or penile fracture, which is uncommon but real and is the reason only specifically trained doctors may administer the injection. Most ruptures happen within two weeks of injection during intercourse or a spontaneous erection, which is why abstaining from all sexual activity for at least two weeks after the modeling procedure is essential. A popping sensation, sudden loss of an erection, severe pain or marked swelling needs same-day emergency assessment. Xiaflex has not been found to cause penile shortening.

参照

1. Gelbard M, Goldstein I, Hellstrom WJG, et al. Clinical efficacy, safety and tolerability of collagenase clostridium histolyticum for the treatment of Peyronie disease in 2 large double-blind, randomized, placebo controlled phase 3 studies. J Urol. 2013;190(1):199–207. PubMed
2. Hellstrom WJG, Tue Nguyen HM, Alzweri L, et al. Intralesional collagenase clostridium histolyticum causes meaningful improvement in men with Peyronie’s disease: results of a multi-institutional analysis. J Urol. 2019;201(4):777–782. PubMed
3. Ziegelmann M, Hu Y, Xiang Q, et al. Incremental treatment response by cycle with collagenase clostridium histolyticum for Peyronie’s disease: a pooled analysis of two phase 3 trials. Urology. 2023;175:126–131. PubMed
4. Cahill EM, Trost L. Factors associated with improved curvature outcomes with collagenase clostridium histolyticum for Peyronie’s disease: results from a large prospective series. J Sex Med. 2025. PubMed
5. Russo GI, Cacciamani G, Cocci A, et al. Comparative effectiveness of intralesional therapy for Peyronie’s disease in controlled clinical studies: a systematic review and network meta-analysis. J Sex Med. 2019;16(2):289–299. PubMed
6. Rosenberg JE, Ergun O, Hwang EC, et al. Non-surgical therapies for Peyronie’s disease. Cochrane Database Syst Rev. 2023;7:CD012206. Cochrane Library
7. U.S. Food and Drug Administration. XIAFLEX (collagenase clostridium histolyticum) prescribing information. DailyMed

免責事項 This content is written and reviewed by Dr. Soarawee Weerasopone, a board-certified urologist at Bangkok Hospital Headquarters. It is intended for educational purposes only and does not constitute medical advice. No diagnosis, advice or prescription is provided through personal messaging channels, direct messages or social media. Always consult a qualified healthcare professional before starting, stopping or changing any medical treatment. In an emergency, attend the nearest emergency department — in Thailand the emergency number is 1669.