warnings and cautions
5 WARNINGS AND PRECAUTIONS • Risk of hypotension, bradycardia, and cardiac failure: Monitor for signs and symptoms of cardiovascular adverse effects. Reduce or discontinue use (5.1, 5.2, 5.3, 5.10) • Risk of exacerbating reactive airway disease (5.5) • Diabetes: May mask symptoms of hypoglycemia and alter glucose levels; monitor (5.6) • Risk of unopposed alpha-agonism and severe hypertension in untreated pheochromocytoma (5.9) • Risk of myocardial ischemia when abruptly discontinued in patients with coronary artery disease (5.12, 5.15) 5.1 Hypotension Hypotension can occur at any dose but is dose-related. Patients with hemodynamic compromise or on interacting medications are at particular risk. Severe reactions may include loss of consciousness, cardiac arrest, and death. For control of ventricular heart rate, maintenance doses greater than 200 mcg per kg per min are not recommended. Monitor patients closely, especially if pretreatment blood pressure is low. In case of an unacceptable drop in blood pressure, reduce or stop esmolol hydrochloride in sodium chloride injection. Decrease of dose or termination of infusion reverses hypotension, usually within 30 minutes. 5.2 Bradycardia Bradycardia, including sinus pause, heart block, severe bradycardia, and cardiac arrest have occurred with the use of esmolol hydrochloride in sodium chloride injection. Patients with first-degree atrioventricular block, sinus node dysfunction, or conduction disorders may be at increased risk. Monitor heart rate and rhythm in patients receiving esmolol hydrochloride in sodium chloride injection [see Contraindications ( 4)] . If severe bradycardia develops, reduce or stop esmolol hydrochloride in sodium chloride injection. 5.3 Cardiac Failure Beta-blockers, like esmolol hydrochloride in sodium chloride injection, can cause depression of myocardial contractility and may precipitate heart failure and cardiogenic shock. At the first sign or symptom of impending cardiac failure, stop esmolol hydrochloride in sodium chloride injection and start supportive therapy [see Overdosage (10)] . 5.4 Intraoperative and Postoperative Tachycardia and/or Hypertension Monitor vital signs closely and titrate esmolol hydrochloride in sodium chloride injection slowly in the treatment of patients whose blood pressure is primarily driven by vasoconstriction associated with hypothermia. 5.5 Reactive Airways Disease Patients with reactive airways disease should, in general, not receive beta-blockers. Because of its relative beta 1 selectivity and titratability, titrate esmolol hydrochloride in sodium chloride injection to the lowest possible effective dose. In the event of bronchospasm, stop the infusion immediately; a beta 2 stimulating agent may be administered with appropriate monitoring of ventricular rate. 5.6 Hypoglycemia Beta-blockers may prevent early warning signs of hypoglycemia, such as tachycardia, and increase the risk for severe or prolonged hypoglycemia at any time during treatment, especially in patients with diabetes mellitus or children and patients who are fasting (i.e., surgery, not eating regularly, or are vomiting). If severe hypoglycemia occurs, patients should be instructed to seek emergency treatment. 5.7 Infusion Site Reactions Infusion site reactions have occurred with the use of esmolol hydrochloride in sodium chloride injection. They include irritation, inflammation, and severe reactions (thrombophlebitis, necrosis, and blistering), in particular when associated with extravasation [see Adverse Reactions ( 6 )] . Avoid infusions into small veins or through a butterfly catheter. If a local infusion site reaction develops, use an alternative infusion site and avoid extravasation. 5.8 Use in Patients with Prinzmetal’s Angina Beta-blockers may exacerbate anginal attacks in patients with Prinzmetal’s angina because of unopposed alpha receptor–mediated coronary artery vasoconstriction. Do not use nonselective beta-blockers. 5.9 Use in Patients with Pheochromocytoma If esmolol hydrochloride in sodium chloride injection is used in the setting of pheochromocytoma, give it in combination with an alpha-blocker, and only after the alpha-blocker has been initiated. Administration of beta-blockers alone in the setting of pheochromocytoma has been associated with a paradoxical increase in blood pressure from the attenuation of beta-mediated vasodilation in skeletal muscle. 5.10 Use in Hypovolemic Patients In hypovolemic patients, esmolol hydrochloride in sodium chloride injection can attenuate reflex tachycardia and increase the risk of hypotension. 5.11 Use in Patients with Peripheral Circulatory Disorders In patients with peripheral circulatory disorders (including Raynaud’s disease or syndrome, and peripheral occlusive vascular disease), esmolol hydrochloride in sodium chloride injection may aggravate peripheral circulatory disorders. 5.12 Abrupt Discontinuation of Esmolol Hydrochloride in Sodium Chloride Injection Severe exacerbations of angina, myocardial infarction, and ventricular arrhythmias have been reported in patients with coronary artery disease upon abrupt discontinuation of beta-blocker therapy. Observe patients for signs of myocardial ischemia when discontinuing esmolol hydrochloride in sodium chloride injection. Heart rate increases moderately above pre-treatment levels 30 minutes after esmolol hydrochloride in sodium chloride injection discontinuation. 5.13 Hyperkalemia Beta-blockers, including esmolol hydrochloride in sodium chloride injection, have been associated with increases in serum potassium levels and hyperkalemia. The risk is increased in patients with risk factors such as renal impairment. Intravenous administration of beta-blockers has been reported to cause potentially life-threatening hyperkalemia in hemodialysis patients. Monitor serum electrolytes during therapy with esmolol hydrochloride in sodium chloride injection. 5.14 Use in Patients with Metabolic Acidosis Beta-blockers, including esmolol hydrochloride in sodium chloride injection, have been reported to cause hyperkalemic renal tubular acidosis. Acidosis in general may be associated with reduced cardiac contractility. 5.15 Use in Patients with Hyperthyroidism Beta-adrenergic blockade may mask certain clinical signs (e.g., tachycardia) of hyperthyroidism. Abrupt withdrawal of beta-blockade might precipitate a thyroid storm; therefore, monitor patients for signs of thyrotoxicosis when withdrawing beta-blocking therapy. 5.16 Use in Patients at Risk of Severe Acute Hypersensitivity Reactions When using beta-blockers, patients at risk of anaphylactic reactions may be more reactive to allergen exposure (accidental, diagnostic, or therapeutic). Patients using beta-blockers may be unresponsive to the usual doses of epinephrine used to treat anaphylactic or anaphylactoid reactions [see Drug Interactions ( 7)].