INFLUENCE OF OLEIC ACID ON THE IN VITRO PENETRATION OF DICLOFENAC SODIUM GEL

Abstract

Diclofenac sodium (DS) is a nonsteroidal antiinflammatory drugs (NSAIDs), that inhibits cyclooxygenase-2 enzyme (COX-2). It has first pass metabolism by 40-50%, because of its short biological half-life, the drug has to be given frequently (Ganiswara, 2005). Dose of DS in gel is 1% (Sweetman, 2007). In peroral use, it may cause the risk of gastrointestinal bleeding, cardiovascular, hypersensitivity reactions and disorders of the central nervous (Katzung, 2002, Chuasuwan, et al., 2008). DS does not penetrate well through skin and cannot reach the effective concentration at the site of action after transdermal application (Mohammed, 2001; Ozguney, et al., 2006). DS partition coefficient in n-octanol-buffer aqua (log P) was 1.1 (Chuasuwan, 2008). Lipophilic nature of the stratum corneum and the hydrophilic nature of the underlying tissues showed that the drug will penetrate the skin should have an optimal balance between the lipophilic and hydrophilic properties. In general, the skin is more permeable to the material which has a partition coefficient (P) in octanol-water between 10-1000 (Michniac-Kohn et al., 2005). Oleic acid enhances the penetration of drugs into the skin by increasing the fluidity of the stratum corneum lipids through the establishment of channels (water channels) (Fang , et al , 2003) This study aimed to know the influence of Oleic Acid (OA) in several concentrations (1%, 3% and 5%) as penetration enhancer on the in vitro penetration of topical DS gel. Furthermore, the physical properties of the topical preparation (organoleptic, pH and viscosity), and DS penetration percutaneously through rat skin . Then observed that in spite of DS assay and penetrate through the rat skin at certain intervals and observed by means of HPLC.