My Daughter Has Only Recently Started Sweating Excessively( She Is

My daughter has only recently started sweating excessively( She is 10 and a half years old) the problem is that she is part of a dance troupe and is becoming increasingly embarrassed by wet underarm marks during competitions. As a teenager myself I suffered from the same problem and used driclor, is there an age restriction on her using this? I'm wondering whether this is a hereditary problem