A low initial botulinum toxin A treatment response does not predict poor long-term outcomes in patients with axillary bromhidrosis.

[PURPOSE] For patients with axillary bromhidrosis, it is not clear that whether a low response to initial botulinum toxin A (BTX-A) treatment is related to poor long-term outcomes.

[PATIENTS AND METHODS] From August 2011 to March 2016, 31 patients with primary axillary bromhidrosis were recruited. They had the duration of efficacy for less than 4 weeks (median, 3 weeks; range, 1-3 weeks) after the first BTX-A injection (50 U per underarm) and were considered to have a low response to BTX-A treatment. The second injection with the same dose was immediately administered once the symptoms recurred. Subsequent sessions were performed with a double dose.

[RESULTS] The duration of efficacy rose significantly to 10 weeks (range, 1-24 weeks) after the second injection (p < .01). Twenty-five patients received the third injection. The resultant duration further increased to 16 weeks (range, 12-26 weeks). No patients reported adverse effects during our follow-up period.

[CONCLUSIONS] For patients with primary axillary bromhidrosis, a low initial BTX-A treatment response does not predict poor long-term outcomes. Immediate reinjection with the same dose and subsequent sessions with a double dose is a safe strategy and can increase the duration of BTX-A therapy.