Healthy adult (New Zealand, Dutch Belt, and Wild) rabbits were infected with rabbit papilloma virus (Shope variety). The resultant papillomas were treated with salicylic acid in a new transdermal drug delivery system utilizing a karaya gum glycol matrix. Biopsy samples of treated papillomas were taken at 1, 2, and 3 weeks after initiation of treatment and examined by electron microscopy. The observed changes during the course of treatment indicated that the karaya gum glycol matrix effectively released salicylic acid into the stratum corneum. Further, the rate of delivery of salicylic acid was such that the desired keratolytic activity was achieved with minimal inflammatory response.