Formulation and Characterization of Emulgel Lornoxicam Containing Lemon Grass Oil as Penetration Enhancer.

Introduction: Emulgel dosage form is an advanced form of transdermal drug delivery. It is a combination of emulsion and gel in a definite ratio. Emulsions are incorporated into the gel with proper mixing. The emulsion present in emulgel can be either oil/water or water/oil, which is thickened by mixing it with a gelling agent.

Materials and methods: On the basis of the solubility of lornoxicam in various oils, a surfactant and a co-surfactant were selected for further research. For the preparation of emulgel, the emulsion was prepared with Smix (surfactant and co-surfactant) in a ratio of 1:2. The prepared emulsion was incorporated into different concentrations of carbapol 934 in a 1:1 ratio to make a homogenous emulgel.

Results: The emulgel was inspected visually to see if it had any phase behaviour, spreadability, or grittiness by applying it to a slide. All formulations were evaluated for pH, physical properties, drug content, spreadability, extrudability, swelling index, viscosity, and centrifugation. Franz diffusion cell was used to perform in-vitro release of formulation with the help of egg membrane. Among all formulations, F3 showed 83% release after 6 hours and showed acceptable physical properties like homogeneity, colour, consistency, pH value, spreadability, extrudability, and drug content.

Discussion: Thus, emulgel can be regarded as a more feasible drug delivery system for hydrophobic drugs (lornoxicam) than the currently marketed formulation. Optimized emulgel formulation consists of a microemulsion of lornoxicam, 1% of carbopol 934, propylene glycol, sodium benzoate, lemon grass oil, glycerin, and distilled water. In the in-vitro release studies, pH 7.4 phosphate buffer emulgel formulation (F3) showed 83% after 6 hours. Emulgel was found to be stable under stable conditions.

Conclusion: The emulgel of the poorly water-soluble drug (lornoxicam) was formulated. The components and their optimum ratio for the formulation of microemulsion were obtained by solubility studies and droplet size analysis. Thus, microemulsion can be regarded as a more feasible dose delivery system for lornoxicam than the currently marketed tablet, capsule, and injection formulations. Optimized microemulsion of lornoxicam was incorporated into the gel base. Therefore, it may be concluded that emulgel of lornoxicam can be used as a controlledrelease dosage form of the drug for local application in rheumatoid arthritis.