Calcium channel antagonist adverse effects

Ueno S, Hara Y. Lambert-Eaton myasthenic syndrome without anti-calcium channel antibody adverse effect of calcium antagonist diltiazem. J Neurol Neurosurg Psychiatry 1992 55(5) 409-10. 

Because calcium channel antagonists may be more effective, have few serious adverse effects, and can be given less frequently than nitrates, some authorities consider them the agents of choice for variant angina. Nifedipine, verapamil, and diltiazem are all equally effective as single agents for... 

Monitoring for major adverse effects should be undertaken they include headache and dizziness with nitrates fatigue and lassitude with /J-blockers and peripheral edema, constipation, and dizziness with calcium channel antagonists. 

Adverse effects include nausea, dizziness, disturbance of balance, vomiting, abdominal pain, diarrhoea and loss of appetite. More rarely, hallucinations, seizures and psychoses occur. Mefloquine should be avoided in patients taking (i-adrenoceptor and calcium channel antagonists for it causes sinus bradycardia quinine can potentiate these and other... 

Mibefradil is a member of a class of calcium antagonists that specifically block the T-type calcium channel. It was marketed as an antihypertensive and antianginal drug with an adverse effects profile similar to that of placebo (1) and a favorable pharmacokinetic profile, allowing once-a-day dosage (2). 

The double whammy—additive detrimental effects and novel adverse reactions Combination therapy takes advantage of synergistic mechanisms of antihypertensive action, but this can also be detrimental, particularly if patients are over-treated, leading to dizziness and orthostatic hypotension. Additive effects of certain combinations can also exacerbate adverse reactions that are common with individual agents. For example, calcium channel blockers and alpha-adrenoceptor antagonists both cause peripheral edema, which can be severe if these agents are used together. 

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