I have dealt with excessive sweating under my arms for YEARS. I have had to wear paper towels under my arm pits and sweated through that within minutes. After using heavy aluminum based deodorants that irrupted my skin and itched horribly I discovered a cure, well almost a cure for under $8.00.

So heres how to get rid of it by 90%. No its not 100% but i am sure you are aware of you have it as bad as I did 90% is darn good enough. Get dove clinical strength. I use the clear tone because it doesn't have heavy perfumes that irritate the skin .
#1 dove clinical strength even tone is scent
#2 shower at night. BEFORE  you go to bed apply generously to armpits, Once again apply before you go to bed
#3 next morning DO NOT WASH OFF OR SHOWER
#4 repeat the next night

Give it 3 or 4 days and you will notice a decrease by 80%. ASstime goes on you will see 90%. Now I do not even use clinical strength. I am able to use regular dove coconut I think, at night before I go to bed.

The key is applying at night and giving the deodorant enough time to absorb into the skin without wearing tight work clothes. Put on something loose at night. That simple and IT WORKS!! Unfortunately I cannot go to the gym and then shower and then go out to eat that same day as I sweat and this only works when I apply the night before I go to bed and DO NOT shower in the morning or wash it off. But hey. I am happy. Hope it works for you. Worst case you just wasted $8.00 and aren't using those irritating deodorants with heavy aluminum that make your pits itch!!