Development and Optimization of Effervescent Tablets of Promethazine

The objective of present study was to develop effervescent tablets of promethazine (PMZ) for the treatment of emesis. Effervescent tablets were prepared by direct compression method and were optimized using 3 2 full factorial design. Amount to sodium starch glycolate(X1) and amount of sodium bicarbonate (X2) were selected as independent variables, whereas disintegration time (Y1), amount of carbon dioxide (Y2) and drug release in 5 minutes (Y3) were selected as dependent variables. All the batches were also evaluated for general post compression evaluation of tablet such asweight variation, thickness, friability and hardness. From the results of design batches, best batch was selected and evaluated for in vivo pharmacokinetic study in a rabbit model. The disintegration time ranged from 58.670.27sec to 228.67 0.67sec while amount of carbon dioxide ranged from 0.10.082 gm to 0.290.061gm in all the design batches. From the results of design batches, batch F9 was selected as optimized batch due to higher amount of carbon dioxide released and faster drug release as compared to other batches. Batch B4 was showing higher AUC and Cmax while lower tmax as compared to drug suspension while performing in vivo study of optimized batch in a rabbit model. The study concluded that the combination of sodium starch glycolate and sodium bicarbonate approach for development of effervescent tablet aids to achieve faster disintegration and faster drug release property for PMZ. INTRODUCTION: Promethazine (PMZ), (RSdimethyl [1-methyl-2-(phenothiazone-10-yl) ethyl] amine hydrochloride), is a firstgeneration antihistamine drug, used in the treatment of motion sickness and emesis associated with a wide variety of chemotherapy and radiotherapy regimens. QUICK RESPONSE CODE DOI: 10.13040/IJPSR.0975-8232.6(12).5077-84 Article can be accessed online on: www.ijpsr.com DOI link: http://dx.doi.org/10.13040/IJPSR.0975-8232.6(12).5077-84 Oral bioavailability of PMZ from conventional tablet formulations is highly variable due to poor gastrointestinal absorption in motion sickness, impaired gastric emptying and extensive first pass metabolism. In emetic condition, loss of drug occurs which causes therapeutic failure, thus retention of an oral dose is essential for better absorption of drugs and their therapeutic actions 1-3 . Tablet formulations are having higher onset of action as compared to liquid formulations and also not appropriate formulation in case of emesis. While liquid dosage form is not preferable for drugs which are having poor stability in solution form or in water. Effervescent formulation can be a better alternative compared to conventional tablet