in vitro dispersion time

The present work describes the formulation development of mouth dissolving tablets of Promethazine HCl with an optimum dispersion time along with sufficient hardness. The formulation employed three different super disintegrants, namely crospovidone (CP), sodium starch glycolate (SSG) and crosscarmellose sodium (CCS), each in three different ratios. Microcrystalline cellulose and mannitol were used as binder and diluent respectively. FT-IR and DSC were used to study the drug-excipient compatibility. Preformulation studies were carried out so as to study the compression characteristics and the flow properties of the powder mix, which was within satisfactory limits. Formulations were made by direct compression method and evaluated for in vitro dispersion time (DT), hardness, friability, wetting time, and in vitro dissolution rate. The effect of DCP and lactose as a diluent was evaluated. All the formulations showed a DT below 4 min. with hardness of 2.9 kg.cm-2 or above. Tablets containing CP at 10%W/W with a hardness of 3.25 kg.cm-2 and DT of 17 S was chosen as the most satisfactory formulation which released the complete drug in 4 min. The other super disintegrants yield tablets of nearly lesser hardness (upto 2.9 kg.cm-2) with higher DT (upto 216 S). DCP and lactose increased the DT without major effect hardness of tablets.