[Toxin treatment of sweat pearls. A review of the treatment of hyperhidrosis with a special view of a new therapy option using botulinum toxin A].

Hyperhidrosis is defined as an excess of sweating beyond the amount needed to cool down elevated body temperature. We distinguish a primary and a secondary form, where an underlying endocrinological or neurological disease is found. The innervation of eccrine sweat glands is sympathetic but the transmitter is cholinergic (ACh). There are variable modalities in the treatment of focal hyperhidrosis, such as topical aluminium chloride application, tapwater iontophoresis, anticholinergic drugs or surgery (axillary sweat gland extraction, liposuction or thoracoscopic sympathectomy). Only recently botulinum toxin (BTX) has been introduced as a therapeutic tool for hyperhidrosis. As BTX inhibits the release of ACh at the cholinergic synapse, perspiration is arrested completely after intradermal injection. BTX is a very potent alternative to the surgical approach in the treatment of hyperhidrosis, though the treatment must be repeated regularly to maintain the effect.