Abstract

FORMULATION AND CHARACTERIZATION OF GASTRORETENTIVE FLOATING TABLETS OF ANTIVIRAL DRUG

Mariyambibi Mandarawala* and Sohel Punasiya

ABSTRACT

Acyclovir is an antiviral drug used for the treatment of herpes simplex virus infections, with an oral bioavailability of only 10-20 %( limited absorption in gastrointestinal tract to duodenum and jejunum.) and half-life of about 3 h, and is soluble only at acidic pH. Floating Drug Delivery Systems (FDDS) have a bulk density lower than gastric fluids and thus remain buoyant in the stomach for a prolonged period of time, without affecting the gastric emptying rate. While the system is floating on the gastric contents, the drug is released slowly at a desired rate from the system. These floating tablets mainly prepared for reduction of lag time and release the drug up to 12 hours and may also increase the bioavailability of the drugs by utilizing the drug to full extent avoiding unnecessary frequency of dosing. The study included formulation of floating tablets using polymer like HPMC K100M, PVP K30 and Sodium bicarbonate. FTIR studies conformed that there was no incompatibility between the polymers and the drug. Tablet preformulation parameters were within the Pharmacopoeias limit. Formulation of D6 was found to be the optimized formulation, regarding all the properties evaluated in order to achieve objectives of this study that included (i) ease of preparation (ii) good buoyancy (iii) high entrapment efficiency (iv) controlled drug release.

Keywords: Acyclovir, Floating drug delivery system, HPMC, PVP K30, Gastroretentive dosage forms.