Related Experiment Video
Updated: Aug 22, 2026

Intravascular Delivery of Biologics to the Rat Kidney
Published on: September 1, 2016
Intentional overdose of Large Animal Immobilon
Joeri Sterken1, Joris Troubleyn, Frank Gasthuys
1Department of Emergency, University Hospital, Vrije Universiteit Brussel, Brussels, Belgium.
Abstract:
We describe a case of voluntary self-injection with Large Animal Immobilon, a veterinary anaesthesia product containing etorphine, a very strong opioid, and acepromazine, a phenothiazine. This resulted in cardiorespiratory arrest and the need for sustained haemodynamic support after resuscitation. Large Animal Immobilon is used under specific conditions only, mainly in zoo and wildlife medicine. Primary toxicological analysis, although guided by the presumed toxin, could only detect a metabolite of acepromazine in the urine. Further analysis was able to show some traces of etorphine. A number of topics are treated, including the apparent potency of the etorphine and the selection of a suitable antidote, taking into account the different properties of the respective agents.
Related Concept Videos
Pharmaceutical Poisoning: Treatment Strategies
Drug Toxicity: Dose-Dependent Reactions
Drug Accumulation During Multiple Dosing: Repetitive IV Injections
Drug Toxicity: Allergic Reactions
Drug toxicity: Idiosyncratic Reactions
Drug Toxicity: Overview

