Durability of botulinum toxin treatment for axillary hyperhidrosis.

OBJECTIVES: Botulinum toxin injection effectively treats axillary hyperhidrosis. Durability estimates of 3-14 months, based on self re-referral may overestimate duration. Our objective was to determine treatment durability by active follow-up of patients.

DESIGN: Audit of current practice.

MATERIALS AND METHODS: Patients presenting with severe primary axillary hyperhidrosis were actively followed up for 24 months after intradermal injections of Botulinum Toxin A (Dysport 120 units/axilla). A 10-point Likert Scale (1=worst imaginable symptoms, 10=absolute resolution) and the Hyperhidrosis Disease Severity Score (HDSS) were used at 1 day and 3, 6, 12 and 24 months. We offered re-treatment when symptoms returned to the pre-intervention state.

RESULTS: We treated 45 patients with a mean age of 29 (15-49) years of whom 36 (78%) were women. The median pre-treatment Likert score (i.q.r.) of 3 (2-3) improved to 10 (10-10) on day 1. Scores at 3 (n=44), 6 (n=43) and 12 (n=39) months were 10 (10-10), 8 (7.5-10), and 7 (5-8) respectively. The median 24-month score was 3 (3-6) for 35 patients, including 11 patients with scores >/=6 who have not required re-treatment. HDSS scores followed a similar pattern.

CONCLUSIONS: Axillary botulinum toxin treatment is durable. Patients experience gradual return of symptoms between 6 and 24 months. A minority do not require re-treatment at this time.