In vitro and In vivo Interactions of Diltiazem with Ibuprofen and Naproxen in Aqueous Medium and Rabbits

Abstract

A common practice in the medical science is the prescription of multiple drugs at a time, which may sometimes be neither safe nor effective and may be deleterious. The present study was aimed to evaluate such a combination of diltiazem with ibuprofen and naproxen. The invitro interaction of diltiazem with ibuprofen and naproxen has been studied at room temperature and at different pH in the aqueous medium by spectroscopic and conductometric methods, and the invivo study was done in the rabbit by measuring blood pressure using a mercury manometer. It has been found that diltiazem formed stable 1 : 1 complexes with ibuprofen and naproxen along with some intermediates. The Ardon’s spectrophotometric method was employed to confirm the formation of 1 : 1 complex and for the calculation of the stability constants. The invivo study was carried out to evaluate the influence of ibuprofen and naproxen on the antihypertensive activity of diltiazem in the rabbit. Concurrent administration of ibuprofen and naproxen with diltizem did not make any significant change in the antihypertensive activity of diltiazem. It is thus inferred that co-administration of diltiazem with ibuprofen and naproxen may be considered as safe and effective.