There are anticholinergics such as Ditropan or Robinul which can help, however the side effects such as dry mouth and dry eyes may be worse to deal with. You can purchase Drysol antiperspirant but it may itch and burn and be uncomfortable. It's definitely worth a try though and should be your first line of defense.
Please don't fall into the trap of having a sympathectomy done (ETS). There are ads all over the internet claiming to be a minimally invasive cure. You could very well end up much, much worse and there is no way to predict who will be left with severe side effects which will be permanent. Some surgeons claim that if you go for the clamping method, it can be reversed. There is no scientific data to support that.