Nicholas V. Nguyen, MD, of the division of dermatology, Akron Children’s Hospital, Ohio, and his associates reported.
Ten patients aged 13-24 years with moderate to severe axillary hyperhidrosis started the study and were treated with 1 g of oxybutynin 3% gel applied to each axilla every morning for 4 weeks. Of the seven patients who completed the study, four had a two-point reduction in the Hyperhidrosis Disease Severity Scale (HDSS) at week 1 and all seven achieved that endpoint at week 4. Of the five patients who also had hyperhidrosis of the palms, four had a two-point reduction in the HDSS at weeks 1 and 4; the remaining patient reported no change. Of the five patients who also had plantar hyperhidrosis, two reported a reduction at weeks 1 and 4, two reported no change, and one had no change at week 1 and experienced worse hyperhidrosis at week 4.
Safety data were available in the seven patients who completed the study and in two others, one lost to follow-up after the first week, and one patient who dropped out of the study because of a severe adverse event. Three patients reported application site irritation, but it was mild to moderate and did not require any intervention. Two patients reported xerostomia, which resolved by itself, and one reported constipation and blurry vision unrelated to the study drug.
One patient developed pyelonephritis on the sixth day of treatment, possibly related to the study drug. “This patient had a history of kidney transplantation, immunosuppression, and recurrent urinary tract infections. For these reasons, the drug should be used with caution in patients with a history of urinary retention or recurrent urinary tract infections,” Dr. Nguyen and his colleagues said.
The manufacturer discontinued the 3% formulation during enrollment, because of business reasons. A large, randomized, placebo-controlled, double-blind trial to address unanswered questions is warranted, the researchers noted. Oxybutynin 10% gel, approved for treating overactive bladder, is still commercially available.
The study was supported by a Society for Pediatric Dermatology pilot project grant and a Colorado Clinical and Translational Sciences Institute grant.
SOURCE: Nguyen NV et al. Pediatr Dermatol. 2018 Jan 15. .