hey man .. I'm 18 , just like you I started loosing my hair at 16.. The thing is I don't want to mess with my hormones.. I mean I seriously consider taking propecia.. but I mean I still need to develop .. for instance my beard it's not full yet , I need to grow a bit but I don't think I will have a decent vertex by the time I'm 21.. for instance where you able to have a full beard since you started taking propecia when you where 18 years old?