Percutaneous absorption and elimination of the penetration enhancer Azone in humans.

The percutaneous absorption and elimination of Azone, a new penetration enhancer, were investigated in humans. The distribution and accumulation of Azone in the skin were studied by means of tape stripping. These studies reveal that pure Azone is poorly absorbed. Furthermore, what little Azone is absorbed appears to be rapidly cleared from the circulation by the kidneys. In order to explain the urinary excretion profile, the formation of at least one metabolite is suggested. No accumulation of Azone in the skin was observed.