Botulinum toxin, a poison used in many chemical weapons, might prove to be a boon for people who perspire excessively. Scientists claim that the chemical can cure excessive perspiration. A disorder called hyperhidrosis makes people sweat excessively. Recently, a team from Julius Maximilian University in Wurzburg, Germany, injected small doses of botulinum toxin called type A into a group of patients. In a week, excess sweating stopped in all of them, the researchers claimed. They believe that the toxin works by blocking parts of the autonomic nervous system linked to perspiration.