Ethosuximide

Ethosuximide
Clinical data
Trade namesZarontin, others
AHFS/Drugs.comMonograph
MedlinePlusa682327
License data
Pregnancy
category
  • AU: D
Routes of
administration		By mouth (capsules, solution)
ATC code
Legal status
Legal status
  • BR: Class C1 (Other controlled substances)[1]
  • US: ℞-only
  • EU: Rx-only[2]
  • In general: ℞ (Prescription only)
Pharmacokinetic data
Bioavailability93%[3]
Metabolismliver (CYP3A4, CYP2E1)
Elimination half-life53 hours
Excretionkidney (20%)
Identifiers
  • (RS)-3-Ethyl-3-methyl-pyrrolidine-2,5-dione
CAS Number
PubChem CID
IUPHAR/BPS
DrugBank
ChemSpider
UNII
KEGG
ChEBI
ChEMBL
CompTox Dashboard (EPA)
ECHA InfoCard100.000.954 Edit this at Wikidata
Chemical and physical data
FormulaC7H11NO2
Molar mass141.170 g·mol−1
3D model (JSmol)
ChiralityRacemic mixture
Melting point64 to 65 °C (147 to 149 °F)
  • O=C1NC(=O)CC1(C)CC
  • InChI=1S/C7H11NO2/c1-3-7(2)4-5(9)8-6(7)10/h3-4H2,1-2H3,(H,8,9,10) checkY
  • Key:HAPOVYFOVVWLRS-UHFFFAOYSA-N checkY
  (verify)

Ethosuximide, sold under the brand name Zarontin among others, is a medication used to treat absence seizures.[4] It may be used by itself or with other antiseizure medications such as valproic acid.[4] Ethosuximide is taken by mouth.[4]

Ethosuximide is usually well tolerated.[5] Common side effects include loss of appetite, abdominal pain, diarrhea, and feeling tired.[4] Serious side effects include suicidal thoughts, low blood cell levels, and lupus erythematosus.[4][5] It is unclear if it has adverse effects on the fetus during pregnancy.[4] Ethosuximide is in the succinimide family of medications. Its mechanism of action is thought to be due to antagonism of the postsynaptic T-type voltage-gated calcium channel.[6]

Ethosuximide was approved for medical use in the United States in 1960.[7] It is on the World Health Organization's List of Essential Medicines.[8] Ethosuximide is available as a generic medication.[4] As of 2019, its availability was limited in many countries, with concerns about price fixing in the United States.[9][10][11]

  1. ^ Anvisa (2023-03-31). "RDC Nº 784 - Listas de Substâncias Entorpecentes, Psicotrópicas, Precursoras e Outras sob Controle Especial" [Collegiate Board Resolution No. 784 - Lists of Narcotic, Psychotropic, Precursor, and Other Substances under Special Control] (in Brazilian Portuguese). Diário Oficial da União (published 2023-04-04). Archived from the original on 2023-08-03. Retrieved 2023-08-16.
  2. ^ "List of nationally authorised medicinal products" (PDF). European Medicines Agency.
  3. ^ Cite error: The named reference bioavailability was invoked but never defined (see the help page).
  4. ^ a b c d e f g "Ethosuximide". The American Society of Health-System Pharmacists. Archived from the original on 21 December 2016. Retrieved 8 December 2016.
  5. ^ a b World Health Organization (2009). Stuart MC, Kouimtzi M, Hill SR (eds.). WHO Model Formulary 2008. World Health Organization. pp. 69, 74–75. hdl:10665/44053. ISBN 9789241547659.
  6. ^ Huguenard, John R. (March 2002). "Block of T -Type Ca2+ Channels Is an Important Action of Succinimide Antiabsence Drugs". Epilepsy Currents. 2 (2): 49–52. doi:10.1046/j.1535-7597.2002.00019.x. PMC 320968. PMID 15309165.
  7. ^ "Drugs@FDA: FDA-Approved Drugs". U.S. Food and Drug Administration. Retrieved 29 December 2020.
  8. ^ World Health Organization (2019). World Health Organization model list of essential medicines: 21st list 2019. Geneva: World Health Organization. hdl:10665/325771. WHO/MVP/EMP/IAU/2019.06. License: CC BY-NC-SA 3.0 IGO.
  9. ^ Cite error: The named reference Hem2019 was invoked but never defined (see the help page).
  10. ^ "Attorney General Tong leads 44-state coalition in antitrust lawsuit against Teva Pharmaceuticals, 19 other generic drug manufacturers, 15 individuals in conspiracy to fix prices and allocate markets for more than 100 different generic drugs" (Press release). Office of the Attorney General of the State of Connecticut. 12 May 2019. Retrieved 5 April 2020.
  11. ^ Cite error: The named reference CA2019 was invoked but never defined (see the help page).