Novel extended-release carbamazepine oral suspension: Formulation, evaluation and drug-release kinetic study

Common dosage forms have a number of drawbacks, including, but not exclusive, glitches in effectiveness, fluctuations in drug plasma concentration and poor patient’s compliance. Such problems can be overcome by formulation of the drug as modified-release dosage forms. Usually, modified-release dosage forms are solid dosage form which are not proper for paediatrics and geriatrics. This research attempts to formulate and evaluate an extended-release carbamazepine oral suspension for paediatrics and geriatrics. Different ratios of Eudragit-L100 (Eud.) and PEG 4000 were used for encapsulation of carbamazepine powder. The selection of the best ratio was determined by dissolution test and FT-IR. The formulated ER suspensions were evaluated for organoleptic properties, pH, relative viscosity, density, sedimentation time, drug content and dissolution test. Additionally, drug release kinetics was studied to determine the possible mechanism of drug release. The best encapsulation ratio was (50:500:1000) PEG: Eud: Carbamazepine. Accordingly, formula 3 (F3) was selected. The evaluation tests showed an acceptable result. Mathematical analysis revealed that drug release kinetics following two kinetic models i.e. Hixson-Crowell and first-order model. The obtained results were encouraged to the possibility for manufacturing of first extended-release carbamazepine oral suspension. More in deep pre-clinical and clinical studies, in addition to production scale-up, are crucial.