I've been on Revivogen for about 72 days, just finished my third bottle (been growing my hair out), and I really didn't want to say anything because I don't want to jinx myself OR give out unreliable information about a product until I've used it for quite a while. That being said, it seems to have slowed down my loss. I've also been on Propecia for over 9 months, but it didn't do anything for me pre-Revivogen, so I don't think it's doing anything for me now. Sure, it's possible it kicked in as soon as I started using Rev, but I doubt it. So, at this point, anyway, I recommend Rev very much.