An Overview of Hyperinsulinemic-Euglycemic Therapy in Calcium Channel Blocker and β-blocker Overdose

Both calcium channel blockers (CCBs) and β blockers (BBs) are associated with fatal substance exposures within the United States. Cases of overdose with these agents have the potential to be both complex and difficult to manage. A variety of pharmacologic treatment options are available for clinicians to use to help mitigate harm from these poisonings. Hyperinsulinemic-euglycemic therapy (HIET) was once regarded as a last-ditch effort to treat patients in highly refractory cases. In recent years, this therapy has become a routine therapy in the treatment of CCB/BB overdose. This article provides a literature review regarding HIET in cases of overdose with CCB and BB agents. Relevant literature articles from 1997-2018 were identified and reviewed using the PubMed and Embase databases. The following search terms were used to identify potential articles: "hyperinsulinemic-euglycemic therapy," "overdose," "calcium channel blocker," "beta blocker," and "insulin." Articles published in the English language were included in this review. A manual search of reference lists was also conducted. Much of the literature is limited to case reports, series, retrospective chart reviews, and small prospective studies. The success rate observed in published case series ranged from 80.4-100%. Regular insulin is most commonly dosed at an initial bolus of 1 unit/kg followed by a regular insulin infusion of 0.5-1 unit/kg/hour. Euglycemia is often maintained using intravenous fluids containing dextrose. Hyperinsulinemic-euglycemic therapy exhibited a promising safety profile, provided close monitoring is conducted. More research is needed to determine optimal strategies for maintaining euglycemia, ideal monitoring parameters, and consistent efficacy goals.