Adverse reactions calcium-channel blockers

Although they are chemically heterogeneous, many adverse effects are common to all calcium channel blockers, predictable from their pharmacological actions. Calcium plays a role in the functions of contraction and conduction in the heart and in the smooth muscle of arteries drugs that interfere with its availability (of which there are many, the calcium channel blockers being the most specific) will therefore act in all these tissues. A few idiosjmcratic and hypersensitivity reactions have also been reported with individual calcium channel blockers. 

Gingival hyperplasia, similar to that seen with phenytoin and ciclosporin, is a rare but well-recognized adverse effect of nifedipine (88). It has also been reported in patients taking felodipine (89,90), nitrendipine (SEDA-16, 200), and verapamil (91), suggesting that this adverse effect is a class effect. Only one case of gingival hyperplasia related to calcium channel blockers was reported to the Norwegian Adverse Drug Reaction Committee up to 1991, despite their widespread use (92). However,... 

Stern R, Khalsa JH. Cutaneous adverse reactions associated with calcium channel blockers. Arch Intern Med 1989 149(4) 829-32. 

Adverse reactions to tlie calcium channel blocMiig dni usually are not serious and rarely require discontinuation of tlie drug therapy. The more conunon adverse reactions include dizziness, li it-headedness, nausea, diarrhea, constipation, peripheral edema, headache, bradycardia, flushing, dennatitis, sMii rash, and nervousness. See tlie Summary Drug Table Antianginal Dni for a more specific listing of tlie adverse reactions of tlie calcium channel blockers. 

The calcium-channel blockers are metabolised by the cytochrome P450 isoenzyme CYP3A4, which can be inhibited by fluoxetine. This results in a marked reduction in the metabolism and clearance of the calcium-channel blockers. The reactions reported appear to be the exaggeration of the adverse effects of these calcium-channel blockers, possibly due to an increase in their levels. 

The manufacturers report that basiliximab has been used with analgesics, antibacterials, antifiingals, antivirals, diuretics, beta blockers and calcium-channel blockers without any increase in adverse reactions. None of the drugs was individually named. ... 

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. 

Adverse reactions to somatostatin analogues have been extensively reported. The asymptomatic effects have been reviewed [23, 34 ]. There are asymptomatic gallstones in 20-40, bradycardia in up to 25%, and conduction abnormalities in 10%. Somatostatin analogues may alter the absorption of other drugs, especially oral hypoglycemic agents, p blockers, calcium channel blockers, and dclosporin, while effects on CYP isoenzymes may alter concentrations of quinidine, terfenadine, and warfarin. Somatostatin analogues... 

Diltiazem hydrochloride is a calcium ion influx inhibitor (slow channel blocker or calcium antagonist). It has generally been indicated for the treatment of angina and, more recently (2), hypertension. Diltiazem hydrochloride is a potent dilator of coronary arteries and has been shown to increase exercise tolerance in man. It is available for dosing as immediate release tablets and as extended or sustained release capsules and is usually well-tolerated. While some adverse reactions have been reported during diltiazem hydrochloride therapy, it is generally considered to be well-tolerated. In most cases, no causal relationship between the events and diltiazem hydrochloride use has yet to be established (1). 

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