Abstract

IN VIVO PHARMACOKINETIC STUDY OF GASTRO RETENTIVE FLOATING MATRIX TABLETS OF NICARDIPINE HYDROCHLORIDE PREPARED BY SINTERING TECHNIQUE

Chandan Mohanty* and K. V. Subrahmanyam

ABSTRACT

The present work involved in-vivo pharmacokinetic evaluation of sintered gastro retentive floating matrix tablets (GRFT) of Nicardipine Hydrochloride in comparison to Nicardipine pure drug and unsintered GRFT of Nicardipine. The objective of the present investigation was to study the effect of sintering technique in development of controlled release dosage form. The pure drug, both formulated unsintered and sintered controlled release GRFT of Nicardipine HCL were tested for in-vivo bioavailability study in healthy male New Zealand rabbits (n=3). The plasma concentrations of Nicardipine HCL drug were determined by a validated HPLC method. From the time versus plasma drug concentration data, various pharmacokinetic parameters (Cmax, Tmax, AUC, KE and T1/2) were estimated. Tmax for pure drug, unsintered and sintered tablets was found to be 1h, 2hr and 4h with Cmax values of 119.33 ± 4.72 ng/ml, 96.33± 3.05 ng/ml and 63.66 ± 2.51 ng/ml respectively. Increase of Tmax values in sintered tablets suggested slow absorption of drug from the formulated sintered tablets and the availability of drug at a controlled manner. An increase of the Elimination half-life (T1/2) and decrease in elimination rate constant (KE) of drug in sintered matrix tablet in comparison to the that of unsintered tablets and pure drug was also observed, indicating the prolonged and controlled systemic availability of drug in biological system. The investigated sintered gastro retentive floating matrix tablets exhibited a remarkable increase in bioavailability due to prolonged plasma residence and could maintain constant plasma level of Nicardipine HCL for more than 16 hr in rabbits.

Keywords: In-vivo, Sintering, Pharmacokinetic Parameters, Gastro retentive floating tablet (GRFT), Nicardipine HCL.