The effects of Azone and capsaicin on the permeation of naproxen through human skin

The permeation of naproxen through excised human skin and isolated perfused rabbit ear skin has been determined. It was found that both Atone and caps aicin enhanced the permeation with an enhancement ratio of up to 4-fold. Th e magnitudes of the effect were similar in human and rabbit skin. The perme ation of naproxen from a saturated solution of the drug through skin pre-tr eated with Atone was similar to that from a commercial preparation (Naprosy n). In the perfused rabbit ear experiments the presence of capsaicin had no effect on the vasodilatation of the blood vessels, inferring that the pene tration enhancement was a direct result of capsaicin influencing the barrie r function of the skin. Structural similarities between Atone and capsaicin were seen using molecular graphics. (C) 1999 Elsevier Science B.V. All rig hts reserved.