Deanship of Scientific Research, University of Gezira
Abstract
Background: Carbamazepine (CBZ) is commonly used in the treatment and control of epilepsy, seizures, and neuropathic pain. Due to its limited water solubility, CBZ have slow and variable absorption following oral administration. Effective CBZ plasma levels are achieved through multiple-dose administration of conventional CBZ tablets which may result in serious side effects because of its narrow therapeutic index and toxicity levels. Objectives: This work aimed at comparing four commercial brands of CBZ tablets (A, B, C and D) manufactured by multinational and national companies including the originator (A) through evaluation of their pharmaceutical equivalence using pharmacoepial and nonpharmacoepial standard tests. Methods: Model-independent approach was used for determination of dissolution efficiency (% D.E) and fit factors. Difference between brands was demonstrated through analysis of difference (f1) and similarity (f2) data. In addition various quality tests including weight variation, thickness, diameter, hardness, friability and disintegration time were carried out. Results: The study revealed that all brands complied with the USP specifications regarding weight variation, friability disintegration and drug content. The amount of drug released within 45 minutes were found satisfactory and ranged from 83.44% to 94.5%. Although clear differences in release profiles exist, all brands released about 90% of the labeled CBZ within 30 minutes which can satisfy the patient need. Only brand B failed to pass the nonpharmacoepial hardness test. Conclusion: Selected brands of CBZ tablets complied with all required pharmacoepial quality specifications