WEDNESDAY, July 12, 2023 -- For patients aged 12 years and older with primary palmar hyperhidrosis (PPHH), 20 percent oxybutynin hydrochloride lotion (20 percent OL) is more effective than placebo for reducing palmar sweat volume, according to a study published in the July issue of the Journal of the American Academy of Dermatology.

Tomoko Fujimoto, M.D., Ph.D., from the Ikebukuro Nishiguchi Fukurou Dermatology Clinic in Tokyo, and colleagues examined the efficacy of 20 percent OL for reducing palmar sweat volume in a randomized trial involving Japanese patients aged 12 years and older with PPHH. Participants received 20 percent OL or placebo (144 and 140, respectively) on both palms once daily for four weeks. Response was defined as a reduction of sweat volume of at least 50 percent from baseline.

The researchers found that the responder rate for sweat volume was significantly higher in the 20 percent OL arm than the placebo arm at week four (52.8 versus 24.3 percent, respectively). There were no serious adverse events reported; none of the adverse events resulted in treatment discontinuation.

"When administered for four weeks, 20 percent OL is effective for the treatment of PPHH and has a favorable safety profile. Therefore, it may represent a promising treatment option for PPHH," the authors write.

Several authors received fees from and others are employees of Hisamitsu Pharmaceutical Co., which funded the study and manufactures the 20 percent oxybutynin hydrochloride lotion.