Detomidine

Detomidine is an imidazole derivative and α₂-adrenergic receptor agonist,^[1] used as a large animal sedative, primarily used in horses. It is usually available as the salt detomidine hydrochloride. It is a prescription medication available to veterinarians sold under various trade names.

Detomidine

Clinical data
AHFS/Drugs.com	International Drug Names
ATCvet code	QN05CM90 (WHO)
Legal status
Legal status	Veterinary use only
Pharmacokinetic data
Elimination half-life	30 min
Identifiers
IUPAC name 4-[(2,3-dimethylphenyl)methyl]-3H-imidazole
CAS Number	76631-46-4 N
PubChem CID	56032
ChemSpider	50586 Y
UNII	7N8K34P2XH
KEGG	D07795 N
ChEMBL	ChEMBL2110829 N
CompTox Dashboard (EPA)	DTXSID00227457
Chemical and physical data
Formula	C12H14N2
Molar mass	186.258 g·mol−1
3D model (JSmol)	Interactive image
SMILES Cc2cccc(Cc1cnc[nH]1)c2C
InChI InChI=1S/C12H14N2/c1-9-4-3-5-11(10(9)2)6-12-7-13-8-14-12/h3-5,7-8H,6H2,1-2H3,(H,13,14) Y Key:RHDJRPPFURBGLQ-UHFFFAOYSA-N Y
NY (what is this?)  (verify)

Use

Currently, detomidine is licensed for use only in non-meat horses in the United States, but it is also licensed for use in cattle in Europe and Australia.^[2][3] Detomidine's withholding period is 12–72 hours for dairy cattle and 2–3 days for meat cattle.^[3]

Properties

Detomidine is a sedative with analgesic properties.^[4] α₂-adrenergic receptor agonists produce dose-dependent sedative and analgesic effects, mediated by activation of α₂ catecholamine receptors, thus inducing a negative feedback response, reducing production of excitatory neurotransmitters. Due to inhibition of the sympathetic nervous system, detomidine also has cardiac and respiratory effects and an antidiuretic action.^[5]

Pharmacology

Detomidine is an α₂-adrenergic receptor agonist that binds at a ratio of 260:1 with imidazoline receptor activity.^[3]

Veterinary use

Detomidine is administered intramuscularly. Oral transmucosal has been investigated and is used in some countries although it has poor bioavailability of around 20–25%.^[3] Intravaginal administration in the horse and alpaca has induced sedation.^[3]

Detomidine administration in sheep activates pulmonary macrophages that damage the endothelium of capillaries and alveolar type I cells. This in turns causes alveolar haemorrhage and oedema causing hypoxaemia.^[3][6][7]

• Medetomidine
• Dexmedetomidine