Sexual side effects can occur when men take Propecia, Proscar, or finasteride.
April 11, 2012: The U.S. Food and Drug Administration (FDA) announced today that it will be updating the label information for Propecia, after the FDA received hundreds of adverse event reports from men who were injured by this drug. The new labels will include more warnings about the risk of persistent sexual side effects. Propecia labels will now warn about the possible risk of libido disorders, ejaculation disorders, and orgasm disorders, problems which often do not resolve when Propecia is discontinued. While taking Propecia, the FDA warns that men may also suffer fertility problems and poor semen quality.
Propecia (finasteride) was approved by the U.S. Food and Drug Administration (FDA) in 1997 to treat male pattern baldness. Finasteride was initially developed under the brand-name Proscar in 5-mg doses. It was used to treat enlarged male prostate. Doctors noticed that one side effect of finasteride was that it also treated male pattern baldness. Merck re-developed finasteride under the brand-name Propecia, and sold it in 1-mg doses to end hair loss and promote hair growth. Both Propecia and Proscar are manufactured and sold by the drug company Merck & Co.
Merck claims low risk of Propecia sexual side effects
When Merck submitted approval safety data to the FDA, the clinical studies found that around 2% of men were expected to suffer sexual side effects, such as Propecia erectile dysfunction, decreased libido, decreased amount of ejaculate. The label warned of these Propecia side effects, but assured men that stopping the medication would resolve the problems.
Swedish study of Propecia erectile dysfunction
In 2008, the Swedish Medical Products Association reported that men who used Propecia may be more likely to suffer from irreversible sexual dysfunction. The organization soon required that Merck updated the safety labeling to include this important risk information. Several other European health authorities also required Merck to make these safety label updates, including the United Kingdom’s Medical and Healthcare Products Regulatory Agency. However, Merck did not make the same safety label updates in the United States until the summer of 2011.
Studies show persistent Propecia sexual side effects
Two scientific studies published in 2011 found evidence that Propecia erectile dysfunction may persist even after men discontinue the drug. In addition to erectile dysfunction, doctors found evidence of other sexual health problems, including decreased libido and problems orgasming. The two studies were conducted by the following doctors:
- Dr. Michael Irwig, of George Washington University School of Medicine, who conducted a study of men who were participating in an online forum for men suffering from sexual health problems. In 2011, Dr. Irwig published a study in the Journal of Sexual Medicine regarding the side effects these men had suffered. Many complained of persistent erectile dysfunction, low sexual desire, and problems with orgasms. Some had suffered the dysfunction for months or years after discontinuing finasteride.
- Dr. Abdulmaged M. Traish, a professor of biochemistry and urology at Boston University School of Medicine, published a study in the March 2011 issue of the Journal of Sexual Medicine. His team searched existing medical literature for reports of sexual dysfunction linked to finasteride. They found that 8% of men reported erectile dysfunction and 4.2% reported reduced libido. This rate was roughly double the rate in men receiving a placebo.