Hyperhidrosis is excessive sweating that commonly affects areas like the armpits, hands, and feet, often leading to discomfort and self-consciousness. Botulinum toxin injections can treat this condition by blocking the nerve signals responsible for sweat production in these areas, significantly reducing sweating.Botulinum toxin injections do not cure hyperhidrosis; your symptoms will go away gradually (usually in about a week) and return gradually. Follow-up injections are required to maintain dryness. These repeat injections may be necessary at intervals varying from 7 to 16 months.