Acetyl L-Carnitine Can Help Straighten Your Penis

Peyronie's Disease Is More Common Than You Think

Unexpected benefit found in this versatile, mind-boosting nutrient

The erect human penis is normally quite straight, although a small degree of curvature - typically upward, and sometimes slightly off to one side or the other - falls well within normal bounds. But what if the curvature becomes painful and perhaps so pronounced that it begins to interfere with normal sexual function?

Such an affliction does exist, and it's painful in more ways than one. Called Peyronie's disease, it strikes primarily men about 40-60 years old, with a surprisingly high incidence in that group that may be as much as 3%.1 Although the cause is unknown, the prevailing theory is that it results from injury during intercourse - not necessarily a dramatic injury, such as penile fracture (which can occur, believe it or not), but more likely a series of microinjuries caused by excessive bending force during intercourse in an awkward position. These repetitive, minor traumas can induce deposits of a protein called fibrin, causing inflammation (and pain) and the formation of a fibrous plaque that can eventually become calcified.

The plaque deposit, which is palpable and scarlike, usually occurs on the dorsal (top) surface of the penis, in a structure called the tunica albuginea (a dense, white, fibroelastic sheath) that encases the two corpora cavernosa - the side-by-side cylindrical regions of spongy tissue that become engorged with blood during an erection. The fibrous tissue may even infiltrate the corpora cavernosa themselves, preventing erection entirely.

In advanced (chronic) cases of Peyronie's disease, the scarring and hardening effect of the plaque deposit, which can grow to over 1 in.2 in area, causes the penis, when it is erect, to become ever more distorted. Typically it curves upward, and often sideways, to an angle of as much as 90º from straight. Intercourse becomes difficult, and finally impossible. Sometimes there is erectile failure, making the question of intercourse moot.

The good news about Peyronie's is that spontaneous reversal occurs in about half the cases in the early (acute) stage of the disease, before it becomes chronic.1 The bad news is that in the other half, it doesn't. Either way, the condition hurts - and if there's one place where a man surely does not want to hurt, that has to be it. Life can be cruel and unusual, but Peyronie's goes beyond that.

A severe case of Peyronie's disease (70-degree curvature) in a 56-year-old man. 
(The Lancet 2001;357:2049-51.)


So, what can be done about Peyronie's disease? The most important thing is not to ignore it because of embarrassment. If you have it, seek professional help, which will be just that - help, not judgment. The condition is much more common than you probably suspected, so you have plenty of company. In the early stages of the disease, the preferred treatment is with oral or intramuscular medication; later on, more aggressive administration of medicine directly to the penis may be required, and surgery is the last resort. All can be helpful.

Among the oral medications that are used for Peyronie's disease is tamoxifen, a drug used primarily for the treatment of breast cancer, but also for a few other disorders, including gynecomastia (swelling and tenderness of male breast tissue). Researchers in Italy recently published the results of a preliminary study* in which tamoxifen was used as the control agent against which to compare the effects of a natural nutritional supplement, acetyl L-carnitine (ALC).2There was reason to believe that ALC might be beneficial for victims of Peyronie's disease, and it was virtually certain that it would lack the side effects that are common with prescription drugs such as tamoxifen.

* The research was done at an institute, Andros Italia, for the study of "andrology," which the institute's Web site describes as the male equivalent of gynecology. Not a bad concept - perhaps it will catch on.


With ALC, there was a 92% 
reduction in pain, and the average 
curvature was reduced from 
15.9º to 8.4º, a 47% drop.

But why use a drug as the control, instead of a placebo? Doesn't that complicate things? Well, yes, but the Italian researchers explain that, if left untreated, chronic Peyronie's disease, which can develop rapidly over a period of months, has a 90% chance of progressing. Under those circumstances, it's considered unethical to deny treatment (by giving a placebo). At the time the study was begun, in 1996, tamoxifen was reputed to be the most active drug for Peyronie's disease.

The study enrolled 48 patients, aged 24-64, who were in either the acute phase of Peyronie's disease (15 men, average age 47) or the early chronic phase (33 men, average age 55), when oral medication is still the treatment of choice. The average size of their plaque deposits (during full erection) at the beginning of the study was 113 mm2(0.175 in.2), as measured by an ultrasound technique. Penile curvature (also at full erection) was measured only in the men with the early chronic stage of the disease; it averaged 15º.

The men were randomly assigned to two groups. One group (8 acute, 16 early chronic) was given tamoxifen (20 mg twice daily), while the other group (7 acute, 17 early chronic) was given acetyl L-carnitine (1 g twice daily), for 3 months. The tamoxifen dose was based on published reports on its therapeutic use; the ALC dose was based on a published report and on a preliminary assessment of efficacy by the researchers.

At the end of the study, only half of the tamoxifen group reported a reduction in erectile pain. By contrast, 92% of the ALC group had reduced pain, a highly significant difference. The effects of therapy on penile curvature were also dramatically different. With tamoxifen, there was no significant reduction. With ALC, however, the average curvature was reduced from 15.9º to 8.4º, a 47% drop. In both groups, the plaque size was reduced - by 23% with tamoxifen and by 44% with ALC. The disease progressed in 54% of those in the tamoxifen group but in only 8% of those in the ALC group. Thus, the benefits realized with ALC treatment were significantly greater, overall, than those produced by tamoxifen.

Tamoxifen produced side effects in six patients: facial skin rash in three, loss of libido in two, and upper-abdominal pain in one. ALC produced no side effects, but it has been reported in other studies that ALC sometimes causes a mild euphoria in long-term therapy for male infertility, peripheral diabetic neuropathies (abnormalities of the nervous system), and Alzheimer's disease.2 As side effects go, that's not a bad one to have, and if you were a man whose Peyronie's disease were being reversed, you might feel rather euphoric in any case.

Actually, the mild euphoria is not unexpected, because ALC is often taken for essentially that purpose in the first place. It is well known to act as a stimulant that improves energy, alertness, and mood within an hour or two of ingestion.3

These effects are probably related to its important role in energy metabolism in the cells' mitochondria, the tiny organelles that act as the body's biochemical power generators.

Who Discovered Peyronie's?

Peyronie's disease is named for the brilliant eighteenth-century French surgeon and teacher François Gigot de la Peyronie, who described the disorder in detail in a treatise on ejaculatory failure in 1743. He reported that "rosary beads" of scar tissue extended the full length of the upper surface of the penis (in one case at least), inducing an upward curvature of the penis during erection.

Peyronie, however, was by no means the first to describe "his" disease. It had been known long before his time - probably since the dawn of time, in fact. In the sixteenth century, the affliction was discussed in correspondence between the great Flemish anatomist Vesalius and his brilliant Italian student Fallopius (yes, he of the Fallopian tubes and other anatomical knowledge about women's sexual parts, including coining of the word vagina).

And in 1587, the Italian anatomist Giulio Cesare Aranzi described the disease as "a rare affection of the genitals in people with excessive sexual intercourse: a little penile tumour palpable like a bean in the flaccid penis causing a deformity similar to a ram horn during erection." Actually, it's not all that rare now - and probably wasn't then either - as the accompanying article points out. Men have traditionally been loath to be forthcoming about this condition, so it has remained a kind of "underground" phenomenon.


Acetyl L-carnitine is derived from L-carnitine, an unusual amino acid that is found mainly in red meat and dairy products, and in most cells of the human body, where it is made from two other amino acids, lysine and methionine. (L-Carnitine was formerly thought to be a vitamin, but since our bodies make it, we now know that it's not.)

The disease progressed in only 
8% of the ALC group. Thus, the 
benefits with ALC treatment were 
significantly greater, overall, than 
those produced by tamoxifen.

The acetyl L-carnitine molecule functions as a "delivery system" for its two principal chemical components. It delivers L-carnitine across cell membranes (which are more permeable to ALC than to L-carnitine itself). L-Carnitine's most vital role in human physiology is to facilitate the transport of fatty acids into mitochondria when they're needed for energy metabolism, and back out again if their concentrations become too high and they become, in effect, toxic.

ALC also delivers acetyl groups to other molecules that need them. When an acetyl group and a choline molecule get together, e.g., the result is the vital neurotransmitter acetylcholine, whose depletion in the brain is a hallmark of Alzheimer's disease. And when an acetyl group reacts with coenzyme A, the product is acetyl-coenzyme A, the most important intermediary in the generation of energy from amino acids, fats, and carbohydrates.

Yet another way in which the acetyl group is beneficial is in a process that may occur in our eyes. In laboratory experiments, ALC has been found to inhibit an age-related degenerative process affecting the lens. It is thought to donate its acetyl group to certain lens proteins called crystallins.4 In so doing, it protects them from damage caused by glycation, a chemical process that leads to deleterious substances aptly called AGEs (advanced glycation end products).

As indicated above, ALC has been found to be helpful in treating Alzheimer's disease.5Studies have demonstrated some positive effects, especially with regard to tasks involving attention and concentration. And a slowing of the rate of deterioration has been observed in various measures of cognitive functions, such as logical intelligence, long-term verbal memory, and selective attention. 

Not surprisingly, ALC has also been shown to be of benefit in curbing the less severe process of age-related cognitive decline, the normal slowing down of mental functions as we grow older.

 Why Does Acetyl L-Carnitine Work?

The Italian researchers speculated on a number of reasons why ALC might have shown such positive effects on Peyronie's disease, presumably through amelioration of the processes of inflammation and fibrosis. Among these possible reasons are that:
  • ALC is an antioxidant and depletes harmful oxygen metabolites.
  • ALC stimulates the breakdown of arachidonic acid, which is a precursor of certain inflammatory substances called leukotrienes, prostaglandins, and thromboxanes.
  • ALC enhances energy metabolism in such a way as to increase the breakdown of histamine, which has inflammatory effects.

Among the reasons why ALC has shown these benefits may be that:

In addition to its mood-enhancing and cognitive function-enhancing abilities, ALC has been shown to have neuroprotective effects. In patients with cerebrovascular disease, it reportedly improves blood flow in the brain. Peripheral nerve function is improved as well, especially in diabetes, for which there is evidence that ALC helps inhibit various peripheral neuropathies. And ALC has been reported to increase sperm motility in men whose sperm shows substandard performance, thus increasing the chances of conception.

If Peyronie's disease afflicts anyone you know, be sure to tell him about acetyl L-carnitine, the nutrient that may be able to help straighten things out.


  1. Hauck EW, Weidner W. François de la Peyronie and the disease named after him. Lancet 2001 Jun 23;357:2049-51.
  2. Biagiotti G, Cavallini G. Acetyl-L-carnitine vs. tamoxifen in the oral therapy of Peyronie's disease: a preliminary report. BJU Int 2001;88:63-7.
  3. Sahelian R. Mind Boosters: A Guide to Natural Supplements That Enhance Your Mind, Memory, and Mood. St. Martin's Griffin, New York, 2000.
  4. PDR for Nutritional Supplements. Medical Economics Company, Inc., Montvale, NJ, 2001.
  5. Pettegrew JW, Klunke WE, Panchalingam K. Clinical and neurochemical effects of acetyl-L-carnitine in Alzheimer's disease. Neurobiol Aging 1995;16:1-4.