From Wikipedia, the free encyclopedia
Clinical data
Trade namesPexion
Other namesAWD 131-138; ELB-138
Routes of
ATCvet code
  • 3-(4-Chlorophenyl)-5-morpholin-4-yl-4H-imidazol-2-one
CAS Number
PubChem CID
CompTox Dashboard (EPA)
ECHA InfoCard100.220.751 Edit this at Wikidata
Chemical and physical data
Molar mass279.72 g·mol−1
3D model (JSmol)
  • C1COCCN1C2=NC(=O)N(C2)C3=CC=C(C=C3)Cl
  • InChI=1S/C13H14ClN3O2/c14-10-1-3-11(4-2-10)17-9-12(15-13(17)18)16-5-7-19-8-6-16/h1-4H,5-9H2

Imepitoin (INN), sold under the brand name Pexion, is an anticonvulsant which is used in veterinary medicine in Europe to treat epilepsy in dogs.[1][2][3][4] It was recently[when?] approved in the United States.[2][3][4] The drug also has anxiolytic effects.[1][2] It was originally developed to treat epilepsy in humans, but clinical trials were terminated upon findings of unfavorable metabolic differences in smokers and non-smokers.[1][2]

Imepitoin acts as a low-affinity (4,350–5,140 nM; relative to Ki = 6.8 nM for diazepam and Ki = 1.7 nM for clonazepam) partial agonist of the benzodiazepine site of the GABAA receptor (up to 12–21% of the maximal potentiation of diazepam, a full agonist of this site).[1] It is the first partial agonist to be approved for the treatment of epilepsy.[1] The drug also dose-dependently blocks voltage-gated calcium channels.[3] It is not a benzodiazepine; instead, it is an imidazolone, and bears some structural similarities to hydantoin anticonvulsants like ethotoin and phenytoin.[1]

See also[edit]


  1. ^ a b c d e f Rundfeldt C, Löscher W (2014). "The pharmacology of imepitoin: the first partial benzodiazepine receptor agonist developed for the treatment of epilepsy". CNS Drugs. 28 (1): 29–43. doi:10.1007/s40263-013-0129-z. PMID 24357084. S2CID 31627280.
  2. ^ a b c d Sean Sanders (29 April 2015). Seizures in Dogs and Cats. Wiley. pp. 209–. ISBN 978-1-118-68970-7.
  3. ^ a b c Curtis W. Dewey; Ronaldo C. da Costa (8 September 2015). Practical Guide to Canine and Feline Neurology. Wiley. pp. 806–. ISBN 978-1-119-06204-2.
  4. ^ a b "Archived copy". Archived from the original on 2019-06-17. Retrieved 2017-09-17.{{cite web}}: CS1 maint: archived copy as title (link)