Formulation, Optimisation and Evaluation of Levodopa and Entacapone Loaded Transdermal Patches for the Treatment of Parkinson’s Disease

Abstract

Parkinson’s disease is an extrapyramidal motor disorder leading to progressive degeneration of neurons in substantia niagra, pars compacta and the dopaminergic tract. The most promising drugs used to treat Parkinson’s disease, i.e., levodopa and entacapoe have very low oral bioavailability because of first-pass metabolism, therefore to increase the bioavailability of levodopa and entacapone, these were incorporated in transdermal patches. Different formulations of the levodopa and entacapone drugs were prepared with different polymeric ratios, by using the solvent casting method and the formulations were evaluated for in-vitro and in-vivo tests, which focus on drug release and drug excipient compatibilities. Various models were applied to ascertain the kinetics of drug release by using in-vitro release data. Nine formulations were prepared and evaluated out of which F6 was found to be the best formulation, which contained HPMC and ethyl cellulose in the ratio of 2:3. It showed drug release of 99.11% in about 12 hours.