RESUMEN
BACKGROUND: Patients with focal hyperhidrosis in multiple areas often report improvement of plantar hyperhidrosis after botulinum toxin A (BTX-A) therapy for palmar hyperhidrosis. OBJECTIVE: To assess sweat production from the soles in patients receiving BTX-A treatment for their palmar hyperhidrosis. PATIENTS AND METHODS: Thirty-six patients with both palmar and plantar hyperhidrosis received 100 U of BTX-A per palm. Sweat production of palms and soles was assessed using a starch iodine test and gravimetry at baseline and 1, 3, and 8 months after treatment. Patients were subjectively assessed using a percentile scale. RESULTS: All patients had significant improvement in their palmar hyperhidrosis that lasted for 6.2 +/- 1.8 months. Gravimetry revealed marginal improvement of plantar hyperhidrosis in 12 patients (from 39.7 +/- 21.3 to 31.5 +/- 18.0 mg/min; p=.01) and statistically significant worsening in 24 patients (from 71.6 +/- 70.60 to 109.94 +/- 82.93 mg/min, p<.001). CONCLUSION: Treatment of palmar hyperhidrosis with BTX-A increased plantar sweating in many patients affected by both palmar and plantar hyperhidrosis in the population under study. Regardless, patients reported satisfaction with the results and were willing to repeat treatment.