Diltiazem cardiovascular effects

The effects of the prototypical calcium channel blockers are seen most prominently in the cardiovascular system (Table 19.1), although calcium channels are widely distributed among excitable cells. The following calcium channel-blocking drugs are clinically the most widely used compounds in this very extensive class of pharmacological agents amlodipine, diltiazem, isradipine, nifedipine, nicardipine, nimodipine, and verapamil. 

It has been suggested that calcium channel blockers can be used to treat cocaine dependence, and some studies have shown reductions in cocaine-induced subjective and cardiovascular responses with nifedipine and diltiazem. The cardiovascular and subjective responses to cocaine have been evaluated in a double-blind, placebo-controlled, crossover study in five subjects pretreated with two dosage of nimodipine (393). Nimodipine 60 mg attenuated the rise in systolic, but not diastolic, blood pressure after cocaine. In three subjects nimodipine 90 mg produced greater attenuation than 60 mg. The subjective effects of cocaine were not altered by either dose of nimodipine. 

Verapamil, nifedipine, and diltiazem lower blood pressure with an efficacy comparable to that achieved by other commonly used agents. Their specific effects on the cardiovascular system are as follows ... 

An isolated report describes acute hyperkalaemia and cardiovascular collapse when dantrolene was given to a patient taking verapamil, but not when he was subsequently given nifedipine. Animal studies have found similar effects with the combination of dantrolene and verapamil or diltiazem, but not with nifedipine or amlodipine. 

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