RiteMED Atenolol Drug Interactions

Anesthetics (e.g., methoxyflurane): Contraindicated with atenolol.
Anti-arrhythmic agents: Class I anti-arrhythmic agents (e.g., disopyramide) and the Class III agent amiodarone may have potentiating effect on atrial conduction time and induce negative inotropic effect. This is seen less frequently with quinidine, class IB agents (e.g., tocainide, mexiletine, lignocaine), class IC agents (e.g., flecainide, propaferone), and the class IV anti-arrhythmic agents.
Calcium channel blockers: Verapamil, diltiazem: Hypotension, bradycardia and asystole may occur particularly in patients with impaired ventricular function and/or sinoatrial or atrioventricular conduction abnormalities. Extreme caution is required if these medicines are to be used concomitantly.
Dihydropyridine calcium antagonists (e.g., nifedipine) may be administered cautiously with beta-blockers. Reduce dosage or discontinue calcium channel blocker if excessive hypotension develops.
Catecholamine-depleting agents (e.g., reserpine): Observe closely for evidence of hypotension and/or marked bradycardia which may produce vertigo, syncope, or postural hypotension.
Clonidine: Beta-blockers may exacerbate the rebound hypertension that may follow after withdrawal from clonidine. If the two drugs are concomitantly administered, the beta-blocker should be withdrawn several days before the gradual withdrawal of clonidine. In replacing clonidine with beta-blocker therapy, the introduction of beta-blockers should be delayed for several days after clonidine administration has stopped.
Digitalis/digitalis glycosides: There have been reports of excessive bradycardia when beta-blockers are used to treat digitalis intoxication.
Insulin and oral hypoglycemics: (see Diabetes and hypoglycemia under Precautions).
Prostaglandin synthetase inhibitors (e.g., ibuprofen, indomethacin): May decrease the hypotensive effects of beta-blockers.
Sympathomimetic agents (e.g., epinephrine): Sympathomimetic agents may counteract the effect of beta-blockers.