Although overall incidence of male breast cancer in clinical trials for finasteride 5 mg was not increased, there are post-marketing reports of breast cancer in association with its use, though available evidence does not provide clarity as to whether there is a causative relationship between finasteride and these cancers. A 2018 meta-analysis found no higher risk of breast cancer with 5α-reductase inhibitors. Some men develop gynecomastia (breast development or enlargement) following finasteride usage. The risk of gynecomastia with 5α-reductase inhibitors is low at about 1.5%. Depressive symptoms and suicidality have been reported. Sexual adverse effects
Use of finasteride is associated with an increased risk of sexual dysfunction including erectile dysfunction, decreased libido and ejaculatory dysfunction. Sexual adverse effects of finasteride and dutasteride have been linked to lower quality of life and ability to maintain an intimate relationship, and can cause stress in relationships.The adverse effect profiles of finasteride are somewhat different for its indications of hair loss and BPH. Finasteride for androgenetic alopecia (hair loss in men)
The most common adverse effects of finasteride taken for hair loss are: decrease in sex drive, erectile dysfunction and decrease in amount of semen. : 17 In addition, finasteride has been reported in case reports to cause sexual problems which persist after stopping the medication. A 2012 update to the FDA label noted reports of decreased sex drive, problems with ejaculation and difficulty achieving an erection which continued after stopping the medication. The update also referenced reports of testicular pain and "male infertility and/or poor quality of semen.
Society and culture
Generic names
Finasteride is the generic name of the drug and its INN, USAN, BAN, and JAN, while finastéride is its DCF. It is also known by its former developmental code names MK-906, YM-152, and L-652,931. Brand names
Finasteride is marketed primarily under the brand names Propecia, for pattern hair loss, and Proscar, for BPH, both of which are products of Merck & Co. There is 1 mg of finasteride in Propecia and 5 mg in Proscar. Mercks patent on finasteride for the treatment of BPH expired in June 2006. Merck was awarded a separate patent for the use of finasteride to treat pattern hair loss and it expired in November 2013. Finasteride is also marketed under a variety of other brand names throughout the world. Athletics
From 2005 to 2009, the World Anti-Doping Agency banned finasteride because it was discovered that the drug could be used to mask steroid abuse. It was removed from the list effective 1 January 2009, after improvements in testing methods made the ban unnecessary. Athletes who used finasteride and were banned from international competition include skeleton racer Zach Lund, bobsledder Sebastien Gattuso, footballer Romário, and ice hockey goaltender José Théodore. Miscellaneous
The U.S. Food and Drug Administration advises that donation of blood or plasma be deferred for at least one month after taking the last dose of finasteride. The UK also has a one-month deferral period.Harold Bornstein, the former personal physician of United States President Donald Trump, stated in 2017 that Trump was taking finasteride to promote hair growth.