Does Finasteride Cause Hair Loss?

Does finasteride cause hair shedding? I’m just starting on fin, I’m 22 and have long hair and I don’t know how bad any potential shedding will be? Like are we talking clumps of hair where it looks like I have bald spots or just excess hair shedding, if fin does cause hair shedding?

I have heard that finasteride can rarely cause shedding in the first couple of months, then it stops. Any shedding that lasts more than 3 months is possibly due to the genetic hair loss you are treating.