Transdermally-delivered oxybutynin (Oxytrol(R) for overactive bladder

Abstract

(1) The oxybutynin patch is a transdermal delivery system, which releases the drug oxybutynin through the skin for the management of overactive bladder. (2) Limited evidence suggests that transdermal delivery of oxybutynin over a short period of time may have efficacy comparable to oral oxybutynin. (3) Recent phase II and III clinical trials supported by the manufacturer suggest a potentially reduced incidence of dry mouth compared to oral oxybutynin. Itching, however, is present in 18% of patients, and the patients' withdrawal rate due to adverse events after 12 weeks is significant (10%). (4) More studies are required to determine the long-term efficacy and safety of the oxybutynin patch for overactive bladder. (5) A New Drug Application for transdermal oxybutynin (Oxytrol(R)) is currently under review at the U.S. Food and Drug Administration. As of October 2001, the oxybutynin patch has not been approved in Canada.