The Synergism of Diltiazem and Nifedipine in Their Antihypertensive Functions in the Animal Model and the Case of Coadministration of Ketotifen Fumerate and Potassium Nitrate with Them

An in vivo study has been carried out to evaluate the synergism of diltiazem and nifedipine on the antihypertensive activity and the effect of ketotifen fumerate and potassium nitrate on this phenomenon of synergism in rabbit. It has been found that the lowering of blood pressure by concurrent administration of diltiazem and nifedipine was not equal to the sum of lowering of blood pressure by individual drug. Concurrent administration of ketotifen fumerate and potassium nitrate with diltiazem or with nifedipine did not make a significant change on the antihypertensive activity of diltiazem or nifedipine. Further considerations and monitoring are to be practiced during concurrent therapy of diltiazem and nifedipine to avoid untoward pharmacological and therapeutic actions related to druginteractions but coadministration of ketotifen fumerate and potassium nitrate with either diltiazem or nifedipine might be regarded as safe and effective.