This drug is used for its side-effect in treating hyperhydrosis patients and post-op hyperhydrosis patients who have compensatory sweating on their backs and chests.
The way this drug works for sweating issues is it decreases (even eliminates sweating) from your waist up. It takes approximately 2-3 hours to totally kick in and it lasts for several hours. Like any drug, if you take too much too often, you can build up a tolerance to it.
While sweating is a good thing in many cases, there may be social situations where you don't want to be sweating like a freak from pinning a gram a gear a week and one could use this drug to control sweating in that type of situation.