cheaper to go to lifeextension.com and order a DHT blood test. You will need two of them. One before, and another at least a month in. If you see a 90% drop in DHT levels, it is dutasteride. Each test is like $250 though. So $500 total. Then you got to worry about whether the stuff stays real, or if they switch suppliers or something.
I strongly suspect my stuff is real because I got hair grafts and there is zero recession between the front hair grafts and the natural hair behind them, even after switching from real proscar after 2 years of use. The only other explanation is that maybe my hairloss stopped on its own. But if that is the case, then why take a real drug I don't know. Fincar cut in 4ths is only $7 per month and no prescription needed. So I will stick with it and just watch the transition line now and then.
When the propecia group got off propecia after a year of use, they lost all new hair and saved hair and ended up where the placebo group was really fast. So I think I would have seen a huge shed if my stuff was fake, since I was on doctor prescribed proscar for a year or two. And I've been on fincar for about 2 years now. During this time, my brother went from a NW4 to a NW5 without meds. It is a little disturbing that I might lose hair if they switch suppliers. But if I see any change at all, it won't take me long to get a prescription, and then a year to regrow it.