Hyperhidrosis is a condition caused by excessive sweating that may not necessarily be related to heat or exercise. Sweating excessively may make clothes soak up water or drip off your hands, disrupting normal daily activities as well as causing social anxiety and embarrassment. Hyperhidrosis can be treated with Botox injections in the underarms, feet or palms. The botulinum toxin blocks the nerve signals causing abnormal sweating, stopping sweat glands from producing too much sweat.