Percutaneous Absorption Enhancer Properties of Lavandula Angustifolia Essential Oil on Percutaneous Absorption of Naproxen Sodium from Topical Gel

Abstract The naproxen bioavailability via percutaneous route is low, and several technologies have been used to overcome the problem. Although the permeation enhancer properties of natural essential oils have been reported, there is no study to show the effectiveness of Lavandula angustifolia essential oil on the percutaneous absorption of naproxen sodium from a topical gel to overcome poor percutaneous absorption of naproxen. To this end, the naproxen topical gel was formulated using Carbopol 940 (as a gelling agent), and several vehicles. The results showed a greater level of penetration into (222.19 ± 24.87 vs. 107.65 ± 6.38 µg/cm 2 ) and across (22.07 ± 4.42 vs. 13.14 ± 2.87µg/cm 2 ) the skin layers for the formulation containing essential oil in comparison with the naproxen gel ( P < 0.05) . A significant antinociceptive property was observed in naproxen topical gel containing 0.5% essential oil in both the first and late phase of the formalin test. The effect was observed in the late phase of the tail-flick test too. In conclusion, the study demonstrated that Lavandula angustifolia essential oil significantly enhanced the percutaneous absorption of naproxen and the analgesic effects.