Finasteride, simply, how does it work?

Looking for a genuine answer since I’m just on the fence about taking and so just won’t to fully understand it before I put it in my body. Want to make sure that the alterations it will make to my bodies chemistry won’t be harmful and if it potentially is I’d like to know also obviously so yah basically my main questions are in the title. Also if anyone could speak on the people who claim it can...

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