Etomidate

Etomidate

Clinical data
Trade names	Amidate, Hypnomidate
AHFS/Drugs.com	Monograph
Pregnancy category	US: C (Risk not ruled out)
Routes of administration	Intravenous
ATC code	N01AX07 (WHO)
Legal status
Legal status	UK: POM (Prescription only) US: ℞-only
Pharmacokinetic data
Protein binding	76%
Metabolism	Ester hydrolysis in plasma and liver
Biological half-life	75 minutes
Excretion	Urine (85%) and biliary (15%)
Identifiers
IUPAC name Ethyl 3-[(1R)-1-phenylethyl]imidazole- 5-carboxylate
CAS Number	33125-97-2 Y
PubChem (CID)	36339
DrugBank	DB00292 Y
ChemSpider	33418 Y
UNII	Z22628B598 Y
KEGG	D00548 Y
ChEMBL	CHEMBL23731 Y
ECHA InfoCard	100.046.700
Chemical and physical data
Formula	C14H16N2O2
Molar mass	244.289 g/mol
3D model (Jmol)	Interactive image
Boiling point	392 °C (738 °F)
SMILES O=C(OCC)c1cncn1C(c2ccccc2)C
InChI InChI=1S/C14H16N2O2/c1-3-18-14(17)13-9-15-10-16(13)11(2)12-7-5-4-6-8-12/h4-11H,3H2,1-2H3 Y Key:NPUKDXXFDDZOKR-UHFFFAOYSA-N Y

Etomidate (USAN, INN, BAN) (marketed as Amidate) is a short-acting intravenous anaesthetic agent used for the induction of general anaesthesia and sedation for short procedures such as reduction of dislocated joints, tracheal intubation, and cardioversion. It was developed at Janssen Pharmaceutica in 1964 and was introduced as an intravenous agent in 1972 in Europe and in 1983 in the United States.

In emergency settings, etomidate is one of the most frequently used sedative hypnotic agents. It is used for conscious sedation and as a part of a rapid sequence induction to induce anaesthesia. It is used as an anaesthetic agent since it has a rapid onset of action and a safe cardiovascular risk profile, and therefore is less likely to cause a significant drop in blood pressure than other induction agents. In addition, etomidate is often used because of its easy dosing profile, limited suppression of ventilation, lack of histamine liberation and protection from myocardial and cerebral ischemia. Thus, etomidate is a good induction agent for people who are hemodynamically unstable. Etomidate also has interesting characteristics for people with traumatic brain injury because it is one of the only anesthetic agents able to decrease intracranial pressure and maintain a normal arterial pressure.

In those with sepsis, one dose of the medication does not appear to affect the risk of death.

Another use for etomidate is to determine speech lateralization in people prior to performing lobectomies to remove epileptogenic centres in the brain. This is called the etomidate speech and memory test, or eSAM, and is used at the Montreal Neurological Institute. However, only retrospective cohort studies support the use and safety of etomidate for this test.

Etomidate suppresses corticosteroid synthesis in the adrenal cortex by reversibly inhibiting 11β-hydroxylase, an enzyme important in adrenal steroid production; it leads to primary adrenal suppression. Using a continuous etomidate infusion for sedation of critically ill trauma patients in intensive care units has been associated with increased mortality due to adrenal suppression. Continuous intravenous administration of etomidate leads to adrenocortical dysfunction. The mortality of patients exposed to a continuous infusion of etomidate for more than 5 days increased from 25% to 44%, mainly due to infectious causes such as pneumonia.