A good antiperspirant is often the first line of defense against hyperhidrosis. If extra-strength antiperspirant does not achieve satisfying improvement, your doctor may prescribe a medical-grade antiperspirant. This product works by temporarily blocking the sweat glands with aluminum chloride hexahydrate. The antiperspirant is not used in the same way as commercial products. If your doctor prescribes antiperspirant, you'll apply it to clean, dry skin before you go to sleep. When you wake up, you'll wash the product off. The prescription antiperspirant is used in this manner daily until you begin to notice less sweating. After that point, you may only need to apply the product once or twice a week.