Merck & Co. first introduced Propecia in 1997 and marketed it successfully as a medication to treat male pattern baldness. It has proved enormously popular among men losing their hair, and Merck has made a fortune on it. Originally approved as a drug to treat prostate enlargement, the discovery that it could also slow hair loss and even regrow hair was a huge boon to the pharmaceutical giant.

Unfortunately, since Propecia came on the market some serious issues and complications have come to light, some of which Merck may have known about while it marketed this drug for hair loss. Complications include sexual dysfunction, but the real issue is that many men have reported that the problem persist long after discontinuing use of the drug. Hundreds of these men have filed lawsuits against Merck, looking for monetary damages.

What is Propecia?

Propecia is the generic drug finasteride. Merck first developed finasteride under the brand name Proscar and got approval from the U.S. Food and Drug Administration (FDA) in 1992 for it to be used to treat benign prostatic hyperplasia, or BPH. BPH is an enlarging of the prostate gland in men. One side effect of treatment with Proscar was found to be hair growth. The dosage amount of Proscar to treat BPH is five milligrams. Merck dropped the dose to one milligram and tested it in treating male pattern baldness. Trials were successful and Merck received approval for Propecia in 1997.

Uses and How it Works

Finasteride is a type of drug that belongs to the class of 5-alpha-reductase inhibitors. 5-alpha reductase is an enzyme that is involved in the production of a hormone called dihydrotestosterone from testosterone. Dihydrotestosterone is implicated in BPH, male pattern baldness, and prostate cancer. Proscar was developed to inhibit the enzyme, and to therefore lower the amounts of dihydrotestosterone in the body.

By reducing dihydrotestosterone, finasteride at a dose of five milligrams, treats the symptoms of BPH, like frequent urination, difficulty urinating, and urinary blockages. It also helps to reduce the need for prostate surgery to treat prostate enlargement.

At the lower dose of one milligram, finasteride marketed as Propecia can treat male pattern baldness. Dihydrotestosterone plays a role in hair loss, so by reducing its amount Propecia can stop hair loss and even stimulate hair growth. Results are usually seen right away, but full effects of Propecia are not seen until a few months after starting it. Propecia does not seem to be able to treat hair loss at the temples, and it cannot be used for hair loss in women or children.

Side Effects

The most common side effects of taking Propecia are related to sexual dysfunction. These include erectile dysfunction, ejaculation disorder, and a decreased libido. It may also cause pain in the testicles, depression, and changes in the breasts. Some men may also experience an allergic reaction to Propecia, which can be serious. Signs of a reaction, which requires immediate medical attention, include a rash, itching, or hives, swelling in the mouth and face, and difficulty breathing.

Propecia is not indicated for use in women, children, or people with liver or kidney damage. Women who are pregnant should be especially cautious around Propecia and should not even handle the medication. It is listed as Category X by the FDA for the potential to cause birth defects. This is the strongest category, reserved for drugs that are known to cause abnormalities in fetuses.

Persistent Sexual Dysfunction

In 2012 the FDA announced that Propecia and Proscar labeling would need to include warnings about sexual dysfunction. The labels already indicated these were possible side effects, but new information had come to light that these side effects may persist even after discontinuation of the drug. The new requirements were that the labels for both drugs must include information that reports were made of persistent libido, ejaculation, and erectile dysfunction and that there were also reports of infertility and poor semen quality, although these did improve after discontinuing the drug.

The FDA made the announcement because of adverse events reports, but also stated that there was no clear clinical evidence to connect the use of finasteride to these persistent issues. The FDA cited 421 post-marketing reports from 1998 to 2011. Fifty-nine of these reports stated that the dysfunctions persisted for up to three months after discontinuing use of Propecia. The FDA also received 251 reports of poor semen quality.

Prostate Cancer

In 2011 the FDA made another announcement regarding the safety of Propecia. Based on a review of trials the FDA concluded that there is a small, but significant risk of developing specific type of prostate cancer, called high-grade prostate cancer, in men taking 5-alpha reductase inhibitors like finasteride. The risk is low, but serious because high-grade prostate cancer is a particularly serious form of the disease.

While clinical trials showed that finasteride generally reduces the risk for developing most forms prostate cancer, it increased the risk of high-grade prostate cancer. This form of the cancer is aggressive and develops quickly. It also tends to spread to other areas of the body. Although the risk is low, it is very serious, and so patients and doctors are urged by the FDA warning to carefully weigh the benefits and risks of finasteride before using or prescribing it.

Breast Cancer

One of the possible, although not common, side effects of using finasteride is changes to the breasts, including enlargement. Although rare, there has been a connection between the use of Proscar, the five milligram dose, and development of breast cancer. The risk seems to be slightly increased for men using Proscar as compared to the general population. Men are encouraged to report any changes in the breasts immediately while taking the medication.

Lawsuits

The incidence of sexual dysfunction as a side effect in users of finasteride is generally low. Most men tolerate the drug well and reap the benefits. However, many men have been adversely affected by Propecia and are suing Merck for not adequately communicating the potential risks. Most importantly, Merck originally claimed that any sexual dysfunction side effects would stop after discontinuation of the drug. For some men the symptoms have persisted and caused great emotional and physical distress. Persistent sexual dysfunction can negatively impact a man’s relationships and general quality of life.

A review of the clinical trials conducted for finasteride used as Propecia to treat hair loss concluded that they were of poor quality. The researchers found that the clinical trial results seemed biased and that they were too limited in the study of the potential risks of using finasteride to treat male pattern baldness. This along with the original assertion that dysfunction problems would not persist could spell trouble for Merck.

Hundreds of lawsuits against Merck have been filed and hundreds of men are waiting to see justice. They accuse Merck of misinforming patients and doctors, marketing a drug in spite of known risks, and conducting inadequate safety trials. They hope to get both justice and compensation to make up for the suffering caused by Propecia use.