Interventional Medications Used for Cardiac Stress Testing (7–12,15–17)
| Drug | Indication | Dose | Pharmacokinetics | Mechanism of action | Contraindications/cautions | Adverse effects/interactions |
| Adenosine | Vasodilator stress | Alternative approaches are 140 μg/kg/min for 6 or 4 min with radiopharmaceutical administered at 3 or 2 min, respectively | Rapid onset, peak < 1 min; half-life < 10 s; duration < 5 min constant infusion; no plasma protein bound | Vasodilation through activation of adenosine receptor A2a | Contraindicated in atrioventricular block, severe bronchospasm or asthma, known hypersensitivity; use with caution in hypotension, unstable angina, oral dipyridamole therapy, and medications that suppress sinoatrial or atrioventricular nodes; long-standing methylxanthines need cessation for 5 half-lives | Adverse effects include chest, neck, jaw, or arm pain, headache, flushing, dyspnea and electrocardiogram changes; bronchospasm is possible, especially in asthmatics; adverse reactions reversed with cessation of infusion; interactions include caffeine/xanthine drugs or foods |
| Dipyridamole | Vasodilator stress | 0.56 mg/kg intravenously in 20–40 mL of saline over 4 min with radiopharmaceutical administered at end of 4-min infusion or 2 min after completion of infusion | 1–2 min until onset; peak at 4 min; half-life of 10–12 h; duration can be prolonged without reversal; 90%–99% plasma protein bound | Inhibition of cellular uptake of adenosine to increase availability of endogenous adenosine; vasodilation through activation of adenosine receptor A2a | As for adenosine | As for adenosine except adverse reactions reversed with aminophylline |
| Regadenoson | Vasodilator stress | 0.4 mg in 5-mL intravenous bolus followed by 5-mL saline flush and immediate administration of radiopharmaceutical | 0.5–2.3 min until onset; duration of 2.3 min; triphasic half-life, with 2–4, 30, and 120 min, respectively; 20%–30% plasma protein bound | Vasodilation through selective activation of adenosine receptor A2a | As for adenosine except potentially more flexible in mild to moderate airway disease | As for adenosine except less bronchoconstriction but does have risk of seizures |
| Dobutamine | Stress testing through increasing oxygen demand | 10 μg/kg/min intravenously, increasing to 20, 30, and 40 μg/kg/min every 3 min | 1–2 min until onset; duration of 10 min; half-life of 2–3 min; 40% plasma protein bound | Synthetic catecholamine β2-adrenoreceptor agonist that produces increased rate and force of contraction | Contraindicated in hypertrophic cardiomyopathy, uncontrolled hypertension, unstable angina, atrial fibrillation, β-blocker use, and known hypersensitivity; use with caution in myocardial infarction and cardiogenic shock; β-blockers need cessation for 5 half-lives | Adverse effects include angina, palpitations, headache, nausea, tachycardia; adverse reactions reversed with cessation of infusion or β-blockers; interactions include blood pressure medications, β-blockers, tricyclic antidepressants, MAOIs, CNS stimulants, potassium-depleting drugs |
MAOI = monoamine oxidase inhibitors.
Duration is period of significant or measurable effect. Some adverse effects are more likely when used therapeutically than in single interventional doses.