Problems with underarm perspiration...?

I'm 15 years old and for about a year or two now I've had excessive sweat in my underarms. I've tried all kinds of deodorant, including clinical strength, and some even just make it worse. I've tried eating healthier and drinking more water but that doesn't work either. The only thing that seems to work is when I don't think about it. The thing is, when I try to not think about it I end up feeling self conscious, wondering if I'm sweating, and eventually end up sweating. I heard of the product Dry-Sol , but I think it's prescription. The sweat really does annoy me. It's uncomfortable and embarrassing and I can't even wear certain things because the sweat will end up dripping through. If you have any suggestions, they're greatly appreciated. Thanks