Effect of environmental temperature on transdermal drug penetration.

The effect of environmental temperature on the penetration from matrix-type transdermal patch of non-steroidal anti-inflammatory drugs (NSAIDs) as model drugs was investigated using in vitro and in silico experiment. The patch was applied on the stratum corneum (SC) side of the skin. The dermal side of the skin was mounted on a diffusion cell. The donor compartment of the diffusion cell was filled with distilled water. The donor temperature was set at 2, 25, 37, and 47 °C, respectively. The receptor compartment was kept at 37 °C and filled with phosphate buffer solution during the experiment. The permeation of the drugs from patch increased with increasing the donor temperature. The rate of permeation increased exponentially with increasing skin surface temperature. The diffusion coefficient in the skin remained almost constant, while the skin surface concentration was correlated with the skin surface temperature. The plasma concentrations in human were simulated by SKIN-CAD(®) together with the in vitro penetration experiment. The plasma concentration quickly changed with varying the environment temperature.