have varied degrees of effect on vasodilation, myocardial contractility, and sinoatrial (SA)-atrioventricular (AV) node function Clinical Considerations Both BBs and CCBs may present with fulminant cardiovascular and neurologic findings after a large overdose Typical presentations of both agents include marked bradycardia and hypotension; particularly with the CCBs, common additional findings are those of abnormal AV node conduction, with AV block or accelerated junctional rhythm However, it is important to note that overdoses of dihydropyridine CCBs (amlodipine, nifedipine, etc.) may present with initial hypotension and reflex tachycardia The CNS may also be affected, with coma and/or convulsions that occur in either category of overdoses, though more commonly seen with BBs as compared to CCBs Metabolic disturbances include hypoglycemia with BBs and hyperglycemia and metabolic acidosis with CCBs Bronchospasm may further complicate BB toxicity in patients with underlying reactive airway disease Management of significant ingestions begins with consideration of aggressive gastric decontamination for both types of agents Administer activated charcoal to patients presenting soon after ingestion if there are no contraindications Sustained-release preparations may cause prolonged effects, and whole bowel irrigation may be considered in this context Bradycardia and hypotension may improve with standard treatment such as atropine, fluid boluses, and direct-acting vasopressors such as norepinephrine; however, many cases prove resistant to these measures Additional therapy includes calcium infusion, which may be beneficial in both CCB and BB ingestions, with the recommended adult initial dose being 10 mL of 10% calcium chloride or 30 mL of 10% calcium gluconate, which may be repeated two or three times as necessary (e.g., an initial pediatric dose of approximately 0.2 mL/kg calcium chloride or 0.6 mL/kg of calcium gluconate) Serum calcium and ionized calcium should be monitored Glucagon increases intracellular cyclic adenosine monophosphate (cAMP) by a mechanism independent of β-receptors and has been used with success to improve heart rate and blood pressure in overdoses of BB agents The usual adult dosing regimen is to mg by IV bolus, which may be repeated to a total dose of 10 mg, followed by infusion at to mg/hr Such dosing translates to 50 to 150 μg/kg boluses and similar amounts per hour for pediatric patients Emesis is a potential side effect of glucagon administration For hemodynamically significant overdose of a CCB, hyperinsulinemia– euglycemia therapy is recommended; this therapy should be guided by a clinician