Isoproterenol Drug Information

Isoproterenol hydrochloride injection is indicated: To improve hemodynamic status in patients in distributive shock and shock due to reduced cardiac output For bronchospasm occurring during anesthesia Isoproterenol hydrochloride injection is a beta-adrenergic agonist indicated: To improve hemodynamic status in patients in distributive shock and shock due to reduced cardiac output For treatment of bronchospasm occurring during anesthesia

The following adverse reactions have been associated with use of isoproterenol. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to estimate their frequency reliably or to establish a causal relationship to drug exposure. Nervous system disorders: Nervousness, headache, dizziness, visual blurring Cardiovascular: Tachycardia, tachyarrhythmias, palpitations, angina, ventricular arrhythmias, Adams-Stokes attacks, pulmonary edema Respiratory: Dyspnea Other: Flushing of the skin, sweating, mild tremors, pallor, nausea Common adverse reactions with isoproterenol include tachycardia and palpitations To report SUSPECTED ADVERSE REACTIONS, contact Nordic Pharma, Inc. at 1-844-267-4641 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.

Table 1. Clinically Relevant Interactions with Isoproterenol Epinephrine Clinical Impact Both drugs are direct cardiac stimulants, and their combined effects may induce serious arrhythmias upon simultaneous administration. Intervention Isoproterenol hydrochloride injection and epinephrine should not be administered simultaneously. Drugs that may potentiate clinical response of Isoproterenol Clinical Impact The effects of isoproterenol may be potentiated by tricyclic antidepressants, monoamine oxidase inhibitors, levothyroxinesodium, and certain antihistamines, notably chlorpheniramine, tripelennamine, and diphenhydramine.

Intervention Monitor hemodynamic parameters in patients who concurrently are taking tricyclic antidepressants, monoamine oxidase inhibitors, levothyroxine sodium and certain antihistamines. Adjust doses appropriately. Drugs that may reduce clinical response of Isoproterenol Clinical Impact The cardiostimulating and bronchodilating effects of isoproterenol are antagonized by beta-adrenergic blocking drugs, such as propranolol.

Intervention Monitor for hemodynamic response and relief of bronchospasm and adjust dose appropriately. Do not administer isoproterenol hydrochloride injection and epinephrine simultaneously due to combined effects may induce serious arrhythmias Concomitant use of tricyclic antidepressants, monoamine oxidase inhibitors, levothyroxine sodium and certain antihistamines; hemodynamic parameters may potentiate a clinical response of isoproterenol Beta-adrenergic blocking drugs may reduce cardiostimulating and bronchodilating effects of isoproterenol See 17 for PATIENT COUNSELING INFORMATION.

Pregnancy Risk Summary Prolonged experience with isoproterenol use in pregnant women over several decades, based on published literature, do not identify a drug associated risk of major birth defects, miscarriage or adverse maternal or fetal outcomes. However, there are risks to the mother and fetus associated with isoproterenol use during labor or delivery (see Clinical Considerations ). The estimated background risk of major birth defects and miscarriage for the indicated population is unknown. All pregnancies have a background risk of birth defect, loss, or other adverse outcomes.

In the United States general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2-4% and 15-20%, respectively. Clinical Considerations Hypotension associated with shock is a medical emergency in pregnancy which can be fatal if left untreated. Delaying treatment in pregnant women with hypotension associated with shock may increase the risk of maternal and fetal morbidity and mortality.

Life-sustaining therapy for the pregnant woman should not be withheld due to potential concerns regarding the effects of isoproterenol on the fetus. Labor and Delivery Isoproterenol usually inhibits spontaneous or oxytocin induced contractions of the pregnant human uterus and may delay the second stage of labor. Avoid isoproterenol during the second stage of labor.

Avoid isoproterenol in obstetrics when maternal blood pressure exceeds 130/80 mmHg. Although isoproterenol may improve maternal hypotension associated with shock, it may result in uterine vasoconstriction, decreased uterine blood flow, uterine atony with hemorrhage, and fetal anoxia.

Pediatric Use Safety and efficacy of isoproterenol in pediatric patients have not been established. Intravenous infusions of isoproterenol in refractory asthmatic children at rates of 0.05-2.7 μg/kg/min have caused clinical deterioration, myocardial necrosis, congestive heart failure and death. The risks of cardiac toxicity appear to be increased by some factors that are especially likely to be present in these patients.

If I.V. isoproterenol is used in children with refractory asthma, patient monitoring must include continuous assessment of vital signs, frequent electrocardiography, and daily measurements of cardiac enzymes, including CPK-MB.

Isoproterenol hydrochloride injection is contraindicated in patients with: tachycardia ventricular arrhythmias angina pectoris Isoproterenol hydrochloride injection is contraindicated in patients with: Tachycardia Ventricular arrhythmias Angina pectoris

Overdosage of isoproterenol can cause tachycardia or other arrhythmias, palpitations, angina, hypotension, or hypertension. In case of overdosage, reduce the rate of administration or discontinue isoproterenol hydrochloride injection until patient’s condition stabilizes. Monitor blood pressure, pulse, respiration, and EKG. It is not known whether isoproterenol hydrochloride is dialyzable.