Abstract

FORMULATION AND EVALUATION OF PULSATILE DELIVERY SYSTEM OF ZOLPIDEM TARTRATE

Venkateswaran Chidambaram Seshadri*, Packiaraj Jeyachandran Manohari, Janakiraman Kunchithapatham, Annamalai Rama and Selvamuthukumar Ramalingam

ABSTRACT

Zolpidem Tartrate is one of the widely used drug to induce sleep for sleep deprived patients. Though once daily formulation and immediate release dosage forms were available there is an unfulfilled need with respect to time based drug delivery. In this research, pulsatile or time based drug delivery system was designed by tablet in tablet / press coated tablet approach. The inner core tablet containing drug made by direct blending and compression process was designed to provide rapid drug release and the outer barrier coat blend (A mixture of clay, wax and polymer as release retardants with hydrophilic polymer as channel former) made by aqueous wet granulation process was designed to provide the necessary lag time prior the drug release. The manufactured tablet shows lag time of 4 hours prior to complete drug release when tested for disintegration time and dissolution. The ratio of clay, wax and polymer and the amount of channel former in the outer barrier coat blend controls the entry of fluid to reach the inner core. The time taken by the fluid to disintegrate/deaggregate the outer barrier coat and reach the inner core tablet is the initial lag time observed in the dissolution. Thus successfully formulated time based drug delivery system of Zolpidem Tartrate 1.75 mg and 3.5 mg which is simple and cost effective made with conventional excipients without employing any pH responsive polymers.

Keywords: Direct blending and compression; Aqueous wet granulation process; Core tablet; Barrier coat blend; Press coated tablet; Tablet in tablet.