
As a physician, drug commercials often grab my attention. I enjoy watching the demolition derby of science colliding with marketing, even though it’s not often clear who won.
You may not recall hearing about Xiaflex, the first Food & Drug Administration (FDA)-approved nonsurgical treatment option for Peyronie’s disease, in which scarring of the penis can cause it to bend. But you might remember seeing a TV ad where a middle-aged couple stands beside a kitchen island over a platter of raw carrots. The woman glances down at a bent one and gives her partner an empathetic knowing look. Later on, we’re shown slow-motion images of a cyclone of misshapen carrots filling the screen. They seem to subtly straighten as they tumble.
Xiaflex — technically known as collagenase clostridium histolyticum — is the product being marketed in this branded “Bent Carrot” campaign, but you won’t find it in the produce aisle. You’ll have to visit a urologist. Until you do, here’s what you should know about Peyronie’s disease.
What causes the curve in Peyronie’s disease?
The tunica albuginea is a thick elastic membrane just under the skin of the penis that helps keep it inflated. It’s the balloon part of the balloon.
Injury to the tunica albuginea causes scarring. The injury is typically caused by micro-trauma sustained during intercourse, or, less commonly, by a sports injury, or a connective tissue or autoimmune disease. Scars don’t behave the same as the healthy tissue they replace, and in this case the required elasticity of the scarred penis tissue is lost.
If you bought a balloon where, due to a manufacturing error, the left side was less elastic than the right side, during inflation the right side would expand faster and more fully, causing the balloon to bend to the left. If the scar is on the top part of the penis, as is most often the case, the penis will curve up during an erection. If the scar contracts, some men can notice a “dent” in their penis.
In the initial phase, which can last anywhere from 6 to 18 months, the injury causes inflammation, pain and tenderness of the penis, even when it is in its off-duty, nonerect form. As the acute injury transitions to a scar, the resting pain may lessen but the penis begins to curve, often leading to painful erections. Erectile dysfunction may develop or become worse, and it doesn’t take a degree in mechanical engineering to postulate that intercourse might become painful, or that one could even have problems urinating.
The degree of curvature is highly variable, but Peyronie’s is more than just which direction — right thigh or left thigh — one’s penis prefers to settle into.
How common is Peyronie’s disease?
I would say that Peyronie’s disease is more common than you think, but I don’t know what you think. One in a hundred adult American males has been officially diagnosed with it, but given men’s natural reluctance to discuss this highly personal injury, the incidence could be higher than that. Researchers have found that 1 in 10 men report symptoms consistent with the diagnosis.
What are the risk factors for being one of the 1 in 10? Besides rowdy sex or sports, the list includes connective tissue diseases like scleroderma or Dupuytren contractures, and autoimmune disorders such as lupus or Sjogren syndrome. The risk of Peyronie’s increases with age, for diabetics with E.D. or for those who have had prostate cancer surgery. A family history of Peyronie’s disease also is listed as a risk factor, although honestly, I don’t see that kind of information as entering family lore: “Now Great Grandpa Festus, he had a particularly bad …” At least not where I’m from.
When to seek treatment, and what is it like?
For a fair number of men, the pain and inflammation of the injury will resolve over a period of months, with little to no curve. So why chase trouble? If the scar is small, not painful, and isn’t causing the kind of a curve that causes problems with sex or urination, it’s probably not worth the pain and bother of having a urologist inject medications into your penis.
Yes, you read that correctly (granted, the injection site is numbed before the shot). This brings us to the star of the Bent Carrot campaign, Xiaflex, an enzyme injection that breaks down the tethering scar tissue. It’s FDA-approved for acute phase Peyronie’s disease, but only if the curve is greater than 30 degrees. (Seriously. Call now to receive a free Xiaflex protractor. Or, as one website handily suggests, find yourself an analog clock, where a 30-degree bend is when the hands are at 1:00).
There are two other injection options — verapamil and interferon alpha-2b — which do seem to work, but don’t yet have the bevy of studies required for FDA approval. Medications are commonly used, and often considered “standard of care,” even though they are not FDA approved for that specific use.
If you’re sensitive about needles being put into sensitive parts, there aren’t a lot of other options. There are a handful of oral medications that may either reduce inflammation or improve blood flow, and though they could improve some symptoms, there are no good studies showing they improve scar size or penile curve. Mechanical traction and vacuum devices that slowly stretch out the scar tissue are being investigated, as is the use of focused, low-intensity electroshock waves, which, by its description, will always be a hard sell.
There are surgical options for Peyronie’s disease, but only for the chronic phase, when the acute injury has resolved. Not to oversimplify, but surgery typically involves either removing the so-called “plaque” of scar tissue, thereby untethering the penis, or leaving the plaque in place but removing a portion of tunica albuginea on the side opposite the scar, which has the effect of straightening things out. If a man has both Peyronie’s and E.D., a penile implant can be considered. Under normal circumstances, the penis becomes erect as blood flow into the penis is increased, while blood flow out is restricted. A penile implant involves placing two balloons, side by side, into the penis, and when they inflate, so does the penis.
Who was Peyronie, and did he have any misgivings about ‘his’ disease?
Since you asked, Dr. Francois Gigot de la Peyronie was a Frenchman who received his “barber-surgeon” diploma in 1695, well before the invention of Medicare. He became quite an accomplished lecturer on anatomy and surgery, and in 1736 gained the honor of being named first surgeon to King Louis XV. He first described the condition that would bear his name in 1743, in a treatise he wrote on ejaculatory failure. Although Peyronie developed a number of techniques that would become part of modern intestinal surgery, penile scarring would be his enduring legacy.
We have no record of whether Dr. Peyronie was pleased with the eponym, but within medicine, it’s long been a sign of academic prestige and respect to have one’s name attached to a disease process, even though laypeople might see the association somewhat more negatively. “Hodgkin’s lymphoma” (as one example) sort of trashed the Hodgkin family name.
Over time, this naming practice has faded, but as a young internist seeking fame and primary-care fortune, I coined the phrase “the Bowron reflex.” This describes the universal urge to get on an elevator before the departing passengers have gotten off. My prediction: Centuries (or even decades) from now, people will remember neither me nor elevators, yet the name Francois Gigot de la Peyronie will live on (but hopefully not.)

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