RESUMEN
BACKGROUND: Primary focal hyperhidrosis is caused by excessive secretion by eccrine sweat glands, usually at the palms, soles and axillae. The underlying mechanism is unclear. In recent years botulinum toxin A has emerged as a useful treatment. Compensatory sweating, which is a major problem in many patients who have undergone transthoracic endoscopic sympathectomy for hyperhidrosis, has only rarely been reported after botulinum toxin. However, this potential side-effect of botulinum toxin treatment has not been systematically examined. OBJECTIVES: To investigate if treatment with botulinum toxin A in hyperhidrotic hands may cause compensatory sweating at other skin locations. METHODS: In 17 patients with a history of palmar hyperhidrosis repeated measurements of evaporation were made before and up to 6 months after treatment of the hands with botulinum toxin A. Recordings were made at 16 skin areas and compared with subjective estimates of sweating. RESULTS: Following treatment, palmar evaporation decreased markedly and then returned slowly towards pretreatment values, but was still significantly reduced 6 months after treatment. No significant increase of sweating was found after treatment in any nontreated skin area. CONCLUSIONS: Successful treatment of palmar hyperhidrosis with botulinum toxin does not evoke compensatory hyperhidrosis in nontreated skin territories.