What would happen if i take fin at 17?

Should i just wait until i’m 18? I have a good amount of hair but i can see thin parts when i pull my hair or especially when i get out the shower. And do i take fin for the rest of my life? I have prescribed finasteride for many 17 year old males. It is safe and contrary to fears of it impacting growth– there is no evidence that it does. Waiting, if you are losing hair now...

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