DESIGN AND EVALUATION OF CONTROLLED RELEASE MUCOADHESIVE BUCCAL TABLETS OF LISINOPRIL

Lisinopril, a drug widely used in the treatment of hypertension. However, its extensive first pass metabolism results in poor bioavailability. The objective of present research work is to design and evaluate the controlled release of mucoadhesive buccal tablets of Lisinopril with a goal to increase the bioavailability, reduce dosing frequency and improve patient compliance. The tablets were prepared using Carbopol‐934, Hydroxy propyl methyl cellulose (HPMC), Hydroxy ethyl cellulose (HEC) as mucoadhesive polymers. Six formulations were developed with varying concentration of polymers. The tablets were evaluated for hardness, weight variation, thickness, percentage of drug content, Surface pH, in­vitro studies like swelling, mucoadhesive strength and drug release. Formulation (F4) containing Carbopol‐934 and HPMC K4M in the ratio of (2 : 4) showed good mucoadhesive strength (36.8) and maximum drug release of 97.1% in 10 hrs. Swelling increase with increase in concentration of HPMC K4M in tablets. Swelling pH was found to be 6.10. Formulation (F4) follows zero‐order drug release. FTIR studied showed no evidence on interaction between drug and polymers. The results indicate that the mucoadhesive buccal tablets of Lisinopril may be good choice to bypass the extensive hepatic first pass metabolism with an improvement in the bioavailability of Lisinopril through buccal mucosa.