Is it safe for kids to do Botox?

First of all, I’m 14 and I’m not talking about injecting my face with Botox for the sake of cosmetics. I have this condition called “hyperhidrosis” which is basically excessive, randomly occurring, sweating under the arms(yes, I know it’s disgusting). Antiperspirants do not work for me and the only other reasonable, non-surgical, procedure to treat this condition is Botox. I have read that this has very high success rates and even though it’s temporary (6–8 months), it is something I need done. I am seeking a dermatologist for this tomorrow, but will I just sound stupid asking them to preform Botox on a 14 year old? Is it illegal or something for my age, because this isn’t just for fun. This is a medical procedure that I could really benefit from.