High-dose insulin euglycaemic therapy (HIET): How high is high enough and what are the risks?

A Dos Santos; S Feris; Z Farina

doi:10.7196/

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Published: 2026-04-23

DOI: https://doi.org/10.7196/

Keywords:

High-dose Insulin Euglycaemic Therapy, HIET, Calcium-channel Blocker Overdose, OD, Overdose

A Dos Santos

Department of Anaesthesia and Critical Care, Greys Hospital, Pietermaritzburg, South Africa

S Feris

Department of Anaesthesia and Critical Care, Greys Hospital, Pietermaritzburg, South Africa; Department of Anaesthesia and Critical Care, University of KwaZulu-Natal, Pietermaritzburg, South Africa

Z Farina

Department of Anaesthesia and Critical Care, Greys Hospital, Pietermaritzburg, South Africa

Abstract

Calcium-channel blockers (CCBs) are widely prescribed in South Africa and are frequently implicated in overdose-related morbidity and mortality. We report a case of amlodipine overdose in a teenager. Her management is notable for the exceptionally high dose of insulin used as part of high- dose insulin euglycaemic therapy (HIET), far exceeding standard protocol. Despite the aggressive dosing, no clinically significant hypoglycaemia or hypokalaemia occurred. The patient showed progressive improvement and was discharged from the intensive care unit on day 3, making a full recovery. This case demonstrates that insulin doses significantly exceeding conventional protocols may be safe and effective in resource-limited settings when supported by experienced staff and close monitoring. More research is needed to guide optimal HIET dosing and safe discontinuation protocols.

Issue

SAJCC Vol. 42 No. 1

Section

Short Reports

This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

Authors retain copyright and grant the journal right of first publication.

Author Biographies

S Feris, Department of Anaesthesia and Critical Care, Greys Hospital, Pietermaritzburg, South Africa; Department of Anaesthesia and Critical Care, University of KwaZulu-Natal, Pietermaritzburg, South Africa

Emergency Medicine Specialist working in Pietermaritzburg Department of Anaesthesia and Critical Care

Z Farina, Department of Anaesthesia and Critical Care, Greys Hospital, Pietermaritzburg, South Africa

Pietermaritzburg Department of Anaesthesia and Critical care Head of Department (HOD)

How to Cite

High-dose insulin euglycaemic therapy (HIET): How high is high enough and what are the risks?. (2026). Southern African Journal of Critical Care, 42(1), e3800. https://doi.org/10.7196/

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