Botulinum toxin A for primary axillary hyperhidrosis: a narrative review

Area of Science:

• Dermatology
• Neurology
• Pharmacology

Background:

• Primary axillary hyperhidrosis (PAH) significantly impacts psychosocial well-being and daily life.
• Botulinum toxin type A (BoNT-A) is a common treatment for PAH, inhibiting acetylcholine release to reduce sweating.

Purpose of the Study:

• To review clinical evidence on BoNT-A efficacy, durability, safety, and quality-of-life outcomes for PAH.
• To compare different BoNT-A formulations, injection techniques, and device-based alternatives.

Main Methods:

• Narrative review of published clinical evidence from 2000 to January 2025.
• Inclusion of randomized trials, prospective cohorts, observational studies, and meta-analyses.
• Comparative analysis of BoNT-A versus energy-based modalities.

Main Results:

• Intradermal BoNT-A consistently achieves >50-80% sweat reduction and improves Hyperhidrosis Disease Severity Scale and Dermatology Life Quality Index scores.
• Treatment effects last approximately 4-7 months with mild, localized adverse events.
• Similar efficacy observed among different BoNT-A formulations with standardized techniques; injection mapping impacts outcomes.

Conclusions:

• BoNT-A is a well-supported first-line injectable therapy for PAH resistant to topical treatments.
• Energy-based modalities offer variable comparative outcomes.
• Further head-to-head and cost-effectiveness studies are warranted.