On March 2, the Examiner broke the story that the Food and Drug Administration was conducting a new safety study of finasteride. Made by drug-giant Merck & Co., the drug is marketed as Propecia (in 1 mg form) as a hair growth drug to combat male pattern baldness and as Proscar (in 5 mg doses) to treat prostate enlargement.

The following email was just received by the Examiner from FDA spokeswoman Stephanie Yao:

 “Since you were previously interested in the topic, I thought you’d like to know that we’ve approved changes to the professional labeling for Propecia (finasteride 1 mg) and Proscar (finasteride 5 mg) to expand the list of sexual adverse events reported to FDA post marketing, as some of these events have been reported to continue after the drug is no longer being used. However, it’s important to note that clear causal links between finasteride and sexual adverse events have not been established.

“We are including this information about these adverse events on the labeling as it may be important to individual patients. Additionally, healthcare professionals and patients should include this information as part of a discussion of risks and benefits of finasteride when determining the best individual treatment options.”

Last year, researchers from the George Washington University and Boston University medical schools published separate studies in the Journal of Sexual Medicine that reported Propecia’s persistent side effects. Those side effects include erectile dysfunction, impotence, greatly reduced libido, testicular pain, problems with orgasms, and gynecomastia – an over-development of the male breast.

“These are very real sexual health issues that are affecting a population of previously healthy men ranging in age from 21 to 46 years old who took Propecia,” says George Washington University Professor Michael S. Irwig, M.D., who led the ground-breaking U.S. research on the drug’s side effects. Of the 71 research participants, 94 percent developed low libido, 92 percent developed erectile dysfunction and decreased arousal, and 69 percent developed problems with orgasm.

“It turns out that almost all had multiple sexual function problems,” said Dr. Irwig. “It’s been very frustrating for a lot of these men because they’ve sought care from medical professionals who are unaware of the risk of persistent sexual dysfunction since it was not originally suggested in the literature.”

Last year, the FDA issued a new warning regarding Propecia’s link to high-grade prostate cancer — the most aggressive and deadly form of the disease — but the agency has remained silent on the permanence of the drug’s severe side effects until now.

GW’s Irwig says it is not known exactly what causes these side effects. What is known is that unlike the vast majority of drugs, whose side effects cease when the drug is discontinued, “finasteride is different because it can actually change the brain’s chemistry. The enzyme 5 alpha reductase is present in many areas of the brain. It is rare for a drug to have the capability to persistently change the brain’s chemistry.”

Amid growing revelations that its hair growth drug causes permanent side effects, Merck took down the drug’s official website Propecia.com and replaced it with directions for reporting negative side effects to the FDA. Now the pharmaceutical giant has quietly relaunched the site.

Propecia.com’s home page now contains “Important Risk Information About PROPECIA,” four paragraphs into which Merck restates its boilerplate language from research conducted in the mid-1990s:

“In clinical studies for PROPECIA, a small number of men experienced certain sexual side effects, such as less desire for sex, difficulty in achieving an erection, or a decrease in the amount of semen. Each of these side effects occurred in less than 2% of men and went away in men who stopped taking PROPECIA because of them.”

Then, in the next paragraph, the company adds:

“In general use, the following have been reported: breast tenderness and enlargement; depression; allergic reactions including rash, itching, hives, and swelling of the lips and face; problems with ejaculation; testicular pain; difficulty in achieving an erection that continued after stopping the medication; and, in rare cases, male breast cancer.”

The warning of ongoing impotence — “difficulty in achieving an erection that continued after stopping the medication”— marks the first time Merck has digitally acknowledged a growing problem among men the world over who have taken Propecia. However, Merck does not cite any sources of the reported side effects introduced by the phrase “In general use,” so it is not known how the company arrived at the conclusion that its drug is causing in some patients what appears to be permanent impotence.

Since March 2, Merck has repeatedly refused the Examiner’s requests for comment.

Known clinically as “Post-Finasteride Syndrome” (for Propecia’s generic name, Finasteride), the condition is marked by a host of sexual, mental and physical side effects — including impotence, Peyronie’s disease and depression — that do not resolve themselves after quitting Propecia, and may be irreversible. With annual sales of more than $400 million, Propecia was approved by the FDA in 1997 for the treatment of male pattern baldness.

“The fact that the FDA has now revised the labeling of Propecia and Proscar to include much more serious side effects has huge implications from a legal standpoint,” says attorney Alan Horwitz, co-founder of Ingerman & Horwitz LLP, whose firm took the initiative to produce an educational brochure and website article achieve on the many hazards of Propecia when no information was forthcoming from Merck or the FDA.

“Now that many more national media outlets have picked up the story that the FDA has expanded the list of sexual adverse events linked to Propecia and Proscar, there are now tens of thousands – if not millions – of formerly unsuspecting finasteride users that are suddenly realizing they may be at risk.”

Says Horwitz: “We have compiled a list of articles and other Propecia research on our website (www..com) designed to provide a wealth of information on finasteride to these men as they begin their discovery of Propecia’s potentially life-changing side effects.”