Chicken1,
Yes the hairs do fall out. The hair goes through 3 phases of growth (not an expert here) but eventually they will die out (and fall out). My fastest results were from waxing or plucking. Those hairs would grow back finer and finer and one day they stopped. The density of area of hair growth also thinned out on my skin and the remaininig hairs were a bit lighter or finer. Although, there's other areas that I never did anything to, and those hairs fell out on their own accord.
I don't know how much spiro is needed for you but the more you take, the more it should work. However there is an increased chance of side effects the larger your dosage is. All I know is that Spiro was helpful, but by far was no miracle cure for my acne or hirsutism. Yet with it corabined with my customized diet, it provided the best results in reducing/preventing unwanted body hair. Depending on where the hair was that was a 25% - 90% reduction. Unfortunately it does nothing for improving the hair growth on my head.
HTH
P.S. Joeh thanks for the info on lasers. That's currently my task. In the distant future, my Daddy actually said he'd pay for it!