Design and Evaluation of Floating Matrix Tablets of Lisinopril Dihydrate

Lisinopril dihydrate (LSP) primarily used in the treatment of hypertension, congestive heart failure and heart attack. Floating matrix tablets of LSP prepared with a view of prolonging gastric residence time with a controlled release mechanism to achieve improved patient compliance, least side effects, better drug therapy and all aspects of an ideal drug delivery system. Floating matrix tablets were prepared by  wet granulation technique using  varying concentrations of different grades of gel forming polymers like HPMC K100, HPMC K15, HPMC K4M with sodium bicarbonate as gas generating agent and evaluated for the physico-chemical parameters, floating lag time, total floating time, in vitro dissolution study and swelling studies. The physico-chemical properties of all the formulations were found to be within the prescribed official limits. FTIR study reveals that there was no interaction between drug and excipients. The amount of drug released from various FDDS formulations was found to be in the order of HPMC K100M > HPMC K15M > HPMC K4M. From among all the formulations, the formulation LF-9 with 30% HPMC K15M showed the best result in terms of the required lag time (82±5 sec) and floating duration of 12 h and releasing 99.5% of the drug in 12 h and is considered as the ideal formulation. The dosage form can control the release, avoid dose dumping and extend the duration of action of a drug with prolonged floating time.