Etomidate
[CAS# 33125-97-2]

Identification

• Classification: API >> Anesthetic agents >> General anesthetics
• Name: Etomidate
• Synonyms: 1-(1-Phenylethyl)imidazole-5-carboxylic acid ethyl ester; Amidate
• Molecular Formula: C₁₄H₁₆N₂O₂
• Molecular Weight: 244.29
• CAS Registry Number: 33125-97-2
• EC Number: 251-385-9
• SMILES: CCOC(=O)C1=CN=CN1[C@H](C)C2=CC=CC=C2

Properties

• Solubility: 63.2 mg/L (25 °C water)
• Density: 1.1±0.1 g/cm³, Calc.^*
• Index of Refraction: 1.562, Calc.^*
• Melting point: 135.44 °C
• Boiling Point: 391.5±17.0 °C (760 mmHg), Calc.^*, 384.70 °C
• Flash Point: 190.6±20.9 °C, Calc.^*

^* Calculated using Advanced Chemistry Development (ACD/Labs) Software.

Safety Data

• Hazard Symbols: GHS07;GHS09 Warning
• Risk Statements: H302-H332-H400
• Safety Statements: P261-P264-P270-P271-P273-P301+P317-P304+P340-P317-P330-P391-P501

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Acute toxicity	Acute Tox.	4	H302
Acute hazardous to the aquatic environment	Aquatic Acute	1	H400
Acute toxicity	Acute Tox.	4	H332
Chronic hazardous to the aquatic environment	Aquatic Chronic	1	H410
Chronic hazardous to the aquatic environment	Aquatic Chronic	2	H411

Discovery and Applications

Etomidate, a short-acting intravenous anesthetic agent, was discovered in the 1960s by Janssen Pharmaceutica. Initially developed as a potential anticonvulsant, its remarkable anesthetic properties were soon recognized. The compound's ability to induce rapid anesthesia with minimal cardiovascular and respiratory depression made it an attractive option for use in medical procedures where rapid onset and offset of anesthesia are desired.

Etomidate is primarily used for the induction of general anesthesia. Its rapid onset of action and short duration make it ideal for procedures such as endotracheal intubation, electroconvulsive therapy (ECT), and brief surgical interventions. Unlike some other anesthetic agents, etomidate minimally affects cardiovascular function, making it suitable for patients with compromised hemodynamics.

In addition to its use in anesthesia, etomidate is employed for sedation in critically ill patients requiring mechanical ventilation or invasive procedures in intensive care settings. Its fast onset and short duration of action allow for precise titration of sedation levels while minimizing the risk of prolonged respiratory depression.

Etomidate has also been investigated for its potential role in the management of status epilepticus, a life-threatening neurological emergency characterized by prolonged seizures. While not commonly used as a first-line treatment, its rapid action and minimal hemodynamic effects make it a consideration in refractory cases where other treatments have failed.

Beyond its clinical applications, etomidate continues to be studied for its pharmacological properties and potential therapeutic uses. Research efforts focus on optimizing its pharmacokinetic profile to enhance its safety and efficacy in various clinical scenarios. Additionally, investigations into its molecular mechanism of action provide insights into the physiology of anesthesia induction and sedation.

Etomidate finds application in veterinary medicine for anesthesia induction in animals undergoing surgical procedures or diagnostic interventions. Its rapid onset and short duration of action make it suitable for use in a variety of veterinary settings, ranging from small animal clinics to large animal surgeries.

References

2024. The Efficacy and Safety of Propofol Versus Etomidate for Endoscopic Retrograde Cholangiopancreatography: A Systematic Review and Meta-Analysis. American Journal of Therapeutics, 31(5).
DOI: 10.1097/mjt.0000000000001705

1998. Stereoselective Effects of Etomidate Optical Isomers on Gamma-aminobutyric Acid Type A Receptors and Animals. Anesthesiology, 88(3).
DOI: 10.1097/00000542-199803000-00022

1977. The Experimental Pharmacology of Etomidate, a New Potent, Short-Acting Intravenous Hypnotic. Anaesthesiology and Resuscitation / Anaesthesiologie und Wiederbelebung / Anesthésiologie et Réanimation, Not applicable.
DOI: 10.1007/978-3-642-66787-9_1