A review of 17 randomized controlled trials (including more than 17,000 patients) demonstrated a nearly twofold increase in sexual, ejaculatory and orgasmic dysfunction in young men using Propecia for male pattern hair loss. At the same time, a recent study demonstrated changes in the levels of certain steroids in cerebrospinal fluid of men taking finasteride for hair loss. These steroids have been shown to influence brain function, and their presence may help explain the profound psychological changes such as depression and suicidality that have been associated with finasteride use. This research should cause us to think more carefully about this commonly encountered medication.
—Potential side effects of the drug Trump reportedly takes for hair loss: The Washington Post, Feb. 3, 2017