Transdermal absorption enhancing effect of the essential oil of Rosmarinus officinalis on percutaneous absorption of Na diclofenac from topical gel

AbstractContext: Rosemary essential oil has been used topically for several purposes (analgesic, anti acne, and anti-inflammatory) in Iranian traditional medicine.Objectives: This investigation aimed to study the effect of essential oil of Rosmarinus officinalis L. (Lamiaceae) on the transdermal absorption of Na diclofenac from topical gel.Material and methods: Diclofenac sodium topical gel was prepared with HPMC K4M and Carbopol 934P as a gelling agent, and several vehicles. The most stable gel was chosen and enhancing effects of the essential oil with different concentrations (0.1, 0.5, and 1.0% w/w) on the permeation of diclofenac were evaluated. The anti-nociceptive effect of preparations was evaluated based on the formalin and tail flick tests in mice.Results: The major constituents of the essential oil were 1,8-cineol (15.96%), α-pinene (13.38%), camphor (7.87%), bornyl acetate (6.54%), verbenone (5.82%), borneol (5.23%), camphene (4.96%), and (E)-caryophyllene (3.8%). Topical diclofenac containing ...