i use NIZORAL SHAMPOO. its for dandruff, (sp) but all it is a topical DHT blocker.
its has done well for me with acne. it should also be pretty good for hairloss cuz it blocks dht. rogaine also, and than ntbm has N2shampoo, it has caffeine and a bunch of other things that will stop/slow hairloss.
if you really wana keep it dont use AAS/PH. if your going to use it regardless go with nizoral/rogaine/n2shampoo.
the nizoral & n2shampoo would both last 2 months per bottle. so factor that into their price.