Aluminum chloride hexahydrate
"I never had a problem with excessive underarm sweating until my second year of college. Then, overnight, my sweat glands went into overdrive. My dermatologist prescribed me Drysol and while it worked a little at first, I found it worked MUCH better once I started applying it with a Swisper cotton pad (as opposed to the toiled paper I had been using). Once I used the cotton pad, my underarms became red and irritated (It kept me awake at night) but the sweating stopped. Now my underarms are completely fine. I apply a little each night to be on the safe side, but I simply don't sweat. I can wear whatever I want without thinking about sweating through the material. For me, Drysol has been a Godsend."