Tried the generic rogaine from wally world since it had good reviews. NEVER AGAIN..I could hear my heart beating in my ears. And it was very hard to catch my breath on occasion. I looked up the half life since i was doing the standard 2 drops per day and cut the dosage back to see if that made things better. It didn't.. I thought about propecia but wanted a natural alternative and looked into saw palmetto and biotin and zinc. My hair filled back in on the crown and temples on these. Just my 2 pennies.