I used rogaine and it helped a great deal. When my hair is trimmed shorter, the thinning area in back isn't noticable now, when it was almost a bald spot back then. When my BARBER told me "just shave your head dude!" I figured all hope was lost. Rogaine helped.
Are you still on the FINA? I *almost* got on it a while back, but in my research learned you tripled your chance of prosate cancer from it - scared me away from it.