I won't get much into the sides because we all know the controversy. That being said I believe some individuals have sides on propecia and wanted to share an idea of mine. Now, we know that finasteride is cumulative so using topical won't help us out much long term. Unless we can find a way to keep the stuff on scalp as much as possible. The topical formulation I propose is Zinc, Finasteride and Caffeine, B6 can also be added to potentiate the effects of Zinc. Zinc can inhibit aromatase via depleting copper, a) Decreased estrogen can technically increase testosterone by not transforming through aromatase enzyme. b) Some believe that decreased estrogen can decrease DHT as DHT may be overproduced due to the high aromatase/estrogen, low testosterone levels. Zinc and B6 can also be used to decrease hair loss via 5ARI or via other mechanisms and I haven't seen anyone whom got sides from them. Caffeine is a vasoconstricter and that may help to keep the finasteride on scalp AMAP. It's also believed to have SHH inducing/PGD2 decreasing effects while it's antiandrogenic effects are a subject of controversy. Hope to get y'all's thoughts!