Development and characterization of sublingual tablet of Lisinopril

Abstract

Lisinopril is the drug of choice in hypertension. Bioavailability of the drug is 25% of orally administered dose. An attempt was made to provide safe medicine meeting pharmacokinetics requirement of plasma concentration by formulating a sublingual tablet of Lisinopril. The Objective of present study is to develop the sublingual tablet of Lisinopril and improve its bioavailability, in view to maximize therapeutic effect of the drug. The directly compressed tablet of Lisinopril was formulated using Mannitol, Micro Crystalline Cellulose and Kyron T-314 as super disintegrant. Formulation (F1-F7) was evaluated for disintegration time and in vitro release study. Further the optimized sublingual formulation (F6) and marketed formulation was subjected to in-vivo comparative bioavailability study using white New Zealand rabbits. It was observed that concentration of Micro Crystalline Cellulose, Kyron T-314 has significant effect on the disintegration time of Lisinopril sublingual tablet formulations. The super disintegrant concentration 5% w/w (Kyron T-314) was found optimum in all tablet formulations. AUC of optimized sublingual tablet and oral tablet are 925.35μg×h/mL and 641.97 μg×h/mL with Cmax of 60.80 μg/mL and 41.21 μg/mL and Tmax of 4 h and 4 h respectively. The bioavailability of optimized sublingual tablet of Lisinopril was improved by 1.44 times as compared to conventional oral marketed tablet of Lisinopril. The present approach of formulating sublingual tablet of Lisinopril would definitely improve bioavailability leading to reduced conventional dose of this drug. The administration of sublingual tablet becoming easy and it will improve patient compliance to therapy for hypertension for pediatrics, geriatric and bed ridden patient.