Poor aqueous solubility and low oral bioavailability of Carvedilol, a novel third generation anti-hypertensive drug
necessitates exploration of formulation strategies to achieve quick onset of action and prolonged drug release from a dosage
form. In the present study, disintegration-accelerated solid dispersion-based matrix tablet of Carvedilol has been designed
with L-HPC LH-11, mannitol and Avicel PH-102. Addition of higher percentage of L-HPC (3.5% w/w) in the tablet
formulation, TSD-Ľ resulted in maximum rate of simulated saliva uptake of 0.568 ± 0.02 mg/sec and minimum
disintegration time of 7mins 10.29 ± 14.45 secs in phosphate buffer (pH-6.8). Fibrous nature of L-HPC leads to enhanced
saliva uptake by wicking action into the porous network of tablet resulting in high swell volume without gelling. Creation of
hydrophilic network promoted the disintegrant activity. However, no improvement in dissolution efficiency and mean
dissolution time for TSD-Ľ could be observed in comparison to the batch, TSD-L. Fitting of drug release data to the kinetic
models showed that the formulation batches obeyed Higuchi kinetics i.e. diffusion of drug occurred from hydrophilic
swellable matrix.
Key words: Hydrophilic swellable matrix, Carvedilol, L-HPC
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