Among other things, in a drug that is used to treat BPH (benign prostatic hyperplasia — a non-cancerous enlargement of the prostate), and male pattern hair loss. It's also sometimes used as a hormone replacement in FtM transgender individuals.

It's widely rumored that President Trump uses it for hair loss, which I suspect is part of why this article was shared, and is being upvoted; this side effect wasn't exactly unknown before this study...