Effect of nonionic surfactants on the percutaneous absorption tenoxicam

The effect of 14 types of nonionic surfactants on the permeation of Tenoxicam (TEN) through guinea pigs from propylene glycol solution was investigated in vitro. The flux of TEN was significantly enhanced by polyoxyethylene alkyl ether and polyoxyethylene monoalkyl carboxylate as hydrophilic surfactants, and by polyglyceryl trialkylate, glyceryl monoalkylate, sorbitan monoalkyl carboxylate and sorbitan trialkyl carboxylate as hydrophobic surfactants. In the presence of these surfactants, the flux was increased about 2 to 4 times, as compared to the flux without them. The mechanism of nonionic surfactant action was analyzed and classified by recent methods. the including HLB of surfactants, the solubility of the drugs in vehicle and the hemolysis of erythrocytes. The results suggested that vital factors in the enhancement of skin permeation by nonionic surfactants include the affinity of the surfactants to the stratum corneum, the solubility of the drugs in vehicle and the penetration of surfactants to the stratum corneum.