Pulsatile

Pulsatile Drug Delivery systems (PDDS) are basically time-controlled drug delivery systems in which the system controls the lag time and drug is released in an immediate or extended fashion. The present study was conducted to develop and evaluate pulsatile release tablets of Rabeprazole sodium for the treatment of peptic ulcers. The compression coated tablets consisted of a core tablet containing drug with superdisintegrant, which was further coated by erodible outer layer consisted of HPMC K15M, ethyl cellulose and Karaya gum. After carrying out preformulation studies, the developed tablets were evaluated for post-compression parameters like weight variation, thickness, hardness, friability, drug content and in-vitro drug release study. The best formulation was selected on the basis of post-compression parameters and was subjected to accelerated stability studies for 1 month. Amongst 6 formulations prepared, C5 produced convincing results with a maximum cumulative drug release of 99.97% in 150 minutes. Also the formulation didn’t show any significant changes during 1 month period of stress testing. By virtue of its release pattern and delivering the drug at the right time, right place and in right amounts, the developed delivery system holds good promises of benefiting the patients suffering from peptic ulcers. The release profile of optimized formulation C5 was close to korsmeyer peppas model. Irrespective of the polymer type and its concentration, the prepared optimized pulsatile tablets showed non fickian (anomalous) release.

The aim of present work was to develop pulsatile release dosage form for chronotherapy of hypertension. Considering the biopharmaceutical, pharmacodynamics reasons of Valsartan and circadian rhythm of hypertension a time controlled rupturable tablet, which allowed the release of Valsartan in time controlled release manner was developed for treating early in the morning surge of blood pressure. Core tablet for formulation were prepared using direct compression technique and evaluated for various parameters like % drug content, hardness, thickness, friability and In-vitro disintegration time. To get desired lag time and release profile to achieve pulsatile delivery tablets were coated with ethyl cellulose: Eudragit L100 (3:1), containing dibutyl phthalate and magnesium stearate. Coated tablet was evaluated for in vitro dissolution study, Drug content and rupture time. Optimization was done by using 32 full factorial design by using conc. of croscarmellose in core and coating level as independent variables and rupture time or lag time as dependent variable. Formulation F-5 was found to optimized formulation containing 5% of superdisintegrant in core tablet and 5 % coating level. From the study it is also concluded that Increase in coating level increases lag time & increase in concentration of superdisintegrant decreases lag time.