What would you rather lose?
Your hair or your ability to perform sexually?
It may seem like an obvious choice, but some men may be making that decision without even knowing it.
A from Northwestern University has highlighted the need for more information about certain popular drugs targeted at male consumers that inadvertently cause erectile dysfunction and other side effects.
Researchers investigated 5α-reductase inhibitors, a class of drug primarily used to treat two conditions in men: androgenetic alopecia (male pattern hair loss) and benign prostatic hyperplasia (BPH), otherwise known as an enlarged prostate.
Neither of these conditions is considered life-threatening.
Hair loss is purely a social status issue while BPH can lead to problems such as frequent urination and bladder control problems.
Finasteride, otherwise known by its trade name, Propecia, and dutasteride (Avodart) are two popular examples of 5α-reductase inhibitors that are commonly prescribed for these conditions.
More serious than reported
Researchers in the Northwestern study say the sexual dysfunction effects of both finasteride and dutasteride are considerably worse than some medical literature suggests.
The current Full Prescribing Information (FPI) for finasteride says that, “(t)here is no evidence of increased sexual adverse experiences with increased duration of treatment,” and that “resolution (of sexual adverse experiences) occurred in men who discontinued therapy.”
Researchers disagree, saying that reporting of adverse sexual issues during clinical trials “was of poor quality” and “systematically biased.”
“Even before any human clinical trials were done, severe sexual dysfunction was a foreseeable consequence of taking finasteride or dutasteride,” Dr. Steven Belknap, research assistant professor of dermatology and medicine at Northwestern and lead author of the study, told Healthline. “If there was meaningful assessment of persistent sexual dysfunction in humans during the clinical development of the these drugs, this does not appear to have been reported in the medical literature, the FPI, or other publicly accessible sources.”
Belknap and his colleagues concluded that 5α-reductase inhibitors are not only linked with erectile dysfunction while patients are using the drug, but that these symptoms persist even after stopping usage—a condition referred to as Persistent Erectile Dysfunction (PED).
In a pool of almost 12,000 men, 167 (1.4 percent) of them developed PED. The median length of time that the symptom persisted was 1,348 days — almost four years — after they stopped use of the drug.
The researchers also concluded that 5α-reductase inhibitor usage was a more accurate indicator of PED in men than many other well-known predictors of the condition, including smoking, alcohol-usage, high blood pressure, and diabetes.
Merck, the developer of Propecia, issued the following statement to Healthline:
“Nothing is more important to Merck than the safety of our medicines and the people who use them. Merck stands behind the demonstrated safety and efficacy profile of PROPECIA (finasteride), which has been prescribed to millions of men since its FDA approval in the U.S. in 1997. Merck conducted well-designed clinical trials on the product and stands behind the results, which were reported to the FDA and regulatory agencies around the world.”
A representative from GlaxoSmithKline, the makers of Avodart, did not respond to a Healthline request for an interview.
A common side effect
Erectile dysfunction is not an unusual side effect for many commonly prescribed drugs today.
Everything from anti-depressants, blood pressure medications, and even non-steroidal anti-inflammatory (NSAIDs) like aspirin can cause some sexual dysfunction.
At this point, no one is asking for 5α-reductase inhibitors to be removed from the marketplace. They are effective at their given purpose.
Researchers say what is important is that those interested in taking these drugs are getting all the facts about them.
For a drug like finasteride, which has existed for over two decades and is estimated to be prescribed to 2.6 million men annually, researchers say that clear and accurate information about its relationship to sexual dysfunction should be more available.
In 2011, reached a similar conclusion in their investigation into finasteride and so-called “post-finasteride syndrome” (PFS). They quoted Dr. Michael Irwig, an endocrinologist at George Washington University as saying “What we do want is for patients and doctors alike to understand the potential risk of persistent problems that may not, in fact, be reversible when you stop this drug.”
Since that article was published, the Food and Drug Administration (FDA) updated their labeling for finasteride in 2012 to expand on sexual adverse effects of the drug, including erectile dysfunction.