Interaction entre Aténolol et chlortalidone et Vérapamil

Control patients with milder ventricular dysfunction, if possible, with optimum doses of digitalis and/or diuretics before verapamil treatment is started [see Drug Interactions ( 7.5 )] .

Beta blockers: reports of excess bradycardia and AV block, including complete heart block; monitor closely ( 7.4 )

Beta Blockers Concomitant therapy with beta-adrenergic blockers and verapamil may result in additive negative effects on heart rate, atrioventricular conduction, and/or cardiac contractility.

Antihypertensive Agents Verapamil administered concomitantly with oral antihypertensive agents (e.g., vasodilators, angiotensin-converting enzyme inhibitors, diuretics, beta blockers) will usually have an additive effect on lowering blood pressure.

A variable effect has been seen when verapamil and atenolol were given together.

Because of its relative beta 1 -selectivity, however, atenolol and chlorthalidone may be used with caution in patients with bronchospastic disease who do not respond to or cannot tolerate, other antihypertensive treatment.

Drug Interactions Atenolol and chlorthalidone may potentiate the action of other antihypertensive agents used concomitantly.

Calcium channel blockers may also have an additive effect when given with atenolol and chlorthalidone.

Amiodarone is an antiarrhythmic agent with negative chronotropic properties that may be additive to those seen with beta-blockers.

Concomitant Use of Calcium Channel Blockers Bradycardia and heart block can occur and the left ventricular end diastolic pressure can rise when beta- blockers are administered with verapamil or diltiazem.