Patients should receive the same basic assessment, investigations, and treatment to include airway and ventilator support, gut decontamination if appropriate, and fluid resuscitation. The management of acute CCB toxicity shares many of the principles of beta-blocker poisoning and readers should consult the section on the management of beta-blocker toxicity.

Ponniah Thirumalaikolundusubramanian, in Heart and Toxins, 2015 8.8.1 Management of CCB Toxicity The high cost and limited availability of glucagon may be the only factors precluding its future clinical acceptance.Ramachandran Meenakshisundaram. Glucagon-treated patients should be monitored for side effects of nausea, vomiting, hypokalemia, and hyperglycemia.

The doses of glucagon required to reverse severe beta-blockade are 50 micrograms/kg iv loading dose, followed by a continuous infusion of 1-15 mg/h, titrated to patient response. Because it may bypass the beta-receptor site, glucagon can be considered as an alternative therapy for profound beta-blocker intoxications. This suggests that glucagon's mechanism of action may bypass the beta-adrenergic receptor site. These effects are unchanged by the presence of beta-receptor blocking drugs. Glucagon increases heart rate and myocardial contractility, and improves atrioventricular conduction. Atropine and isoproterenol have been inconsistent in reversing the bradycardia and hypotension of beta-blocker overdose. Medical complications of beta-blocker overdose include hypotension, bradycardia, heart failure, impaired atrioventricular conduction, bronchospasm and, occasionally, seizures. The effects of glucagon in reversing the cardiovascular depression of profound beta-blockade, including its mechanism of action, onset and duration of action, dosage and administration, cost and availability, and side effects are reviewed. Two cases of severe beta-blocker overdose are presented that were treated successfully with glucagon therapy. Can't read entire article without subscription. I haven't read all of article yet to see complete answer.

Glucagon antidote for beta blocker