FORMULATION AND EVALUATION OF NIOSOMAL TRANSDERMAL PATCH OF METHYLDOPA

Gopika Suresh* and Ambili M. V.

ABSTRACT

Niosomes are utilized for drug delivery to specific sites to achieve desired therapeutic effects and also these are promising vehicles for effective transdermal drug delivery. Transdermal drug delivery is less invasive method which offers smooth, controlled and steady delivery of medication. Methyldopa is a central alpha-2 receptor agonist used in the management and treatment of hypertension. It has a low bioavailability of 25% and short half-life of 105 minutes, hence it is suitable drug for developing a sustained release formulation. It is incompletely absorbed from GIT following oral administration, also having extensive first pass metabolism, hence it is a suitable candidate for transdermal patch. The present research work was aimed to develop an optimized formulation of niosomal transdermal patch of Methyldopa and its evaluation for overcoming the problems associated with the oral administration of the drug. Varying concentrations of polymers Eudragit RS-100 and HPMC were used based on the DOE statease version 13 software. In vitro dissolution studies were conducted for niosomes to determine the optimized formulation. The optimized niosomal formulation follows Zero order kinetics indicating sustained release upto 12 hours. The in vitro skin permeation conducted for transdermal patch of methyldopa and it was found to be highest for the formulation F12. Using a numerical optimization tool, 7 sets of optimal solutions were identified. Among these, the best combination was 296.722mg of Eudragit RS- 100 and 105.360mg of HPMC with a desirability factor of 1.0. The skin irritation study of optimized formulation showed that no detectable skin reactions were occurred. This study showed that the Niosomal Transdermal patch could effectively enhance the continuous and sustained delivery of methyldopa, potentially leading to bioavailability and better therapeutic effects.

Keywords: Transdermal drug delivery system, Methyldopa, Eudragit RS-100, HPMC.