Developments in the epidemiology of calcium channel blocker poisoning and implications for management.

PURPOSE OF REVIEW

The aim of this study was to outline recent developments in calcium channel blocker (CCB) poisoning. The dihydropyridine CCB amlodipine is commonly prescribed in the United States, and amlodipine poisoning is increasing in frequency, presenting new challenges for clinicians because current paradigms of CCB poisoning management arose from literature on non-dihydropyridine agents.

RECENT FINDINGS

Amlodipine is now the most common CCB involved in poisoning. High-dose insulin is a potent inotrope and vasodilator; as such, it should be used cautiously, and typically in conjunction with vasopressors, as it theoretically may worsen vasodilation in amlodipine poisoning. High-dose insulin is best used when some degree of cardiogenic shock is suspected. Venoarterial extracorporeal membrane oxygenation utilization in CCB poisoning appears to be increasing, but high flow rates may be needed to combat amlodipine-induced vasoplegia. Intravenous lipid emulsion cannot be routinely recommended but may have a role in peri-arrest situations. Adjunct treatments such as angiotensin II, methylene blue, and hydroxocobalamin offer theoretical benefit but warrant further study.

SUMMARY

Amlodipine causes most cases of CCB poisoning and can induce both cardiogenic and distributive shock through multiple mechanisms. Clinicians should tailor treatment to suspected shock etiology, be aware of adjunct treatments for refractory shock, and consult an expert in poisoning.