Formulation and evaluation of controlled porosity osmotic pump-based tablet of tramadol hydrochloride

Abstract

Introduction: Extended-release formulation of tramadol hydrochloride based on osmotic technology was developed and evaluated. The effect of different formulation variables, namely level of swellable polymer in the core and membrane weight gain, was studied. Drug release was found to be affected by the level of swellable polymer in the core formulation. Tramadol release was inversely proportional to the level of swellable polymer and membrane weight. Drug release from the developed formulations was independent of pH and agitation intensity. Results: The manufacturing procedure was found to be reproducible, and formulations were stable after 3 months of accelerated stability studies.