Abstract

DESIGN, FORMULATION AND CHARACTERIZATION OF VENLAFAXINE HYDROCHLORIDE EXTENDED RELEASE MULTIPARTICULATE SYSTEMS

Ajay Babu CH.*, Maddala Sumathi, M. Varalakshmi, K. Tirumala Devi and M. Prasada Rao

Abstract

The main objective of present investigation is to formulate and evaluate the extended release pellets of venlafaxine hydrochloride a weakly basic and antidepressant drug belongs to serotoninnorepinephrine reuptake inhibitor class having high permeability and high solubility. Rational use of the selection of dosage form is to minimize variation in residence time, less susceptible to dose dumping, to facilitate accurate delivery of small quantity of potent drug, reduced potential side effects without lowering drug bio-availability. Extended release pellets of venlafaxine hydrochloride were prepared employing different concentrations of eudragit, ethylcellulose, hypromellose and surelease in different combinations as a rate retarding polymer by using drug layering technique. The quantity of polymers to achieve the desired extended drug release about 20 hours and the similarity with the reference product was determined. Totally 8 formulations were prepared and are evaluated for hardness, friability, drug content, In-vitro drug release. From the Results it was concluded that all the formulations were found to be within the Pharmacopoeial limits and the In-vitro dissolution profiles of all formulations were fitted in to different Kinetic models, the statistical parameters like intercept (a), slope (b) & regression coefficient (r) were calculated.. Formulation F8 containing combination of 10% ethyl Cellulose N-50, 13.9% polyethylene gylcol-6000 and 13.6% hypromellose, is the most similar formulation when compared with that of marketed product. The optimized formulation follows first order kinetics and Higuchi’s model, and hence, the mechanism of drug release was found to be diffusion controlled.

Keywords: Venlafaxine hydrochloride, Extended Release, pellets, Ethylcellulose, Eudragit.