If you are concerned about excessive underarm sweat you might be suffering from Hyperhidrosis, my brother had the condition.
Hyperhidrosis is excessive sweating not related to heat. You will sweat even if it's cold. My brother had excessive hand, armpit, and feet sweating. It was so bad he was embarassed to shake hands and didn't want to meet new people or go to social functions. He was permanently with dark sweat stains on his shirts.
It's a common problem and treatments include botox injections, and even surgery!
I don't know how bad your underarm sweating is (whether it causes public embarrassment and / or hinders social interaction), but before you take any drastic actions I suggest you visit stop excessive sweating and start living .
They offer excellent advice and a completely natural method to stop excessive sweating. I can recommend the site as it's where my brother went to cure his condition.
Anyway, hope that helps, and I hope you manage to stop your excessive underarm sweat.
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