Men under the age of 40 who use finasteride for alopecia are at risk for suicide if they develop persistent sexual adverse effects and insomnia.

An important pattern of symptoms was common among all cases who committed suicide in the setting of finasteride use: insomnia and persistent sexual dysfunction after medication discontinuation. Insomnia and fatigue/tiredness were some of the most debilitating symptoms… Men under 40 years of age who use finasteride for alopecia are at risk of suicide if they develop persistent sexual adverse effects and insomnia.

—Finasteride and Suicide: A Postmarketing Case Series: Dermatology, January 14, 2020