Research: FORMULATION AND In-vitro EVALUATION OF GASTRORETENTIVE DRUG DELIVERY SYSTEM FOR ACYCLOVIR

Floating matrix tablets of acyclovir were developed to prolong gastric residence time and increase its bioavailability. In the present investigation it was thought worthwhile to develop a gastric floatingdrug delivery system of Acyclovir to improve the efficacy of dosage form. Acyclovir is a potent antiviral drug with low toxicity used in treatment of herpes simplex infection & varicella zoster infection. It has maximum absorption in stomach and upper part of small intestine. Due to low gastric retention time, the bioavailability of drug is low as large portion of drug misses the absorption window. The tablets were prepared by direct compression technique, using polymers such as Hydroxypropylmethylcellulose (HPMC, Methocel K100M), Carbopol and Sodium alginate alone or in combination. Sodium bicarbonate and Citric acid was incorporated as a gas-generating agent. The effects of sodiumbicarbonate and citric acid on drug release profile and floating properties were investigated. All the tablets passed the compendial tests and other tests like weight variation, drug content, hardness,friability.The floating time was found to be more than 12 hrs. All the tablets showed the floating lag time of less than 10minute. Thedissolution study was carried out in 0.1 N HCL using USP type II apparatus.