Cardiac glycoside calcium channel blockers

ACE inhibitors can be administered with diuretics (qv), cardiac glycosides, -adrenoceptor blockers, and calcium channel blockers. Clinical trials indicate they are generally free from serious side effects. The effectiveness of enalapril, another ACE inhibitor, in preventing patient mortaUty in severe (Class IV) heart failure was investigated. In combination with conventional dmgs such as vasodilators and diuretics, a 40% reduction in mortaUty was observed after six months of treatment using 2.5—40 mg/d of enalapril (141). However, patients complain of cough, and occasionally rash and taste disturbances can occur. 

Calcium channel blockers interact with cardiac glycosides. The main mechanism is inhibition of digoxin renal tubular secretion by inhibition of P glycoprotein. In a review of the interactions of calcium channel blockers with digoxin, in which their clinical relevance was assessed, it was concluded that serious consequences can be prevented by careful monitoring, especially in patients whose serum digoxin concentration is already near the upper end of the therapeutic range (174). 

Anorexia, nausea, vomiting, visual disturbances, and the cardiac effects seen in acute toxicity may be seen. In chronic exposures, patients may not demonstrate the classic finding of hyperkalemia, which is frequently seen in acute exposures. Decreased renal function may interfere with clearance of the glycosides. Patients may be more sensitive to the effects of their squill remedies if they are on medication that also slows AV conduction such as quinine, beta blockers, or calcium channel blockers. 

Dmgs used to treat arrhythmias are cardiac glycosides, P-blockers, calcium channel blockers, lidocaine and amiodarone. 

II. BRONCHODIIATORS - montelukast, theophylline 12. CARDIAC GLYCOSIDES -digitoxin 13. CALCIUM CHANNEL BLOCKERS - felodipine, nifedipine, nimodipine, nisoldipine, verapamil... 

Volume loss, venodilation, and arteriolar dilation are likely to result in hypotension with reflex tachycardia. In contrast, hypotension accompanied by bradycardia should suggest intoxication by sympatholytic agents, membrane-depressant drugs, calcium channel blockers, or cardiac glycosides or the presence of hypothermia. 

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