Primidone

Primidone
Clinical data
Trade namesLepsiral, Mysoline, Resimatil, others
Other namesdesoxyphenobarbital, desoxyphenobarbitone
AHFS/Drugs.comMonograph
MedlinePlusa682023
License data
Pregnancy
category
Routes of
administration		By mouth
Drug classAnticonvulsant, barbiturate
ATC code
Legal status
Legal status
Pharmacokinetic data
Bioavailability~100%[4]
Protein binding25%[4]
MetabolismLiver
Elimination half-lifePrimidone: 5-18 h,
Phenobarbital: 75-120 h,[4]
PEMA: 16 h[5]
Time to reach steady state:
Primidone: 2-3 days,
Phenobarbital&PEMA 1-4weeks[6]
ExcretionKidney
Identifiers
  • 5-Ethyl-5-phenyl-1,3-diazinane-4,6-dione
CAS Number
PubChem CID
DrugBank
ChemSpider
UNII
KEGG
ChEBI
ChEMBL
CompTox Dashboard (EPA)
ECHA InfoCard100.004.307 Edit this at Wikidata
Chemical and physical data
FormulaC12H14N2O2
Molar mass218.256 g·mol−1
3D model (JSmol)
  • O=C1NCNC(=O)C1(c2ccccc2)CC
  • InChI=1S/C12H14N2O2/c1-2-12(9-6-4-3-5-7-9)10(15)13-8-14-11(12)16/h3-7H,2,8H2,1H3,(H,13,15)(H,14,16) checkY
  • Key:DQMZLTXERSFNPB-UHFFFAOYSA-N checkY
  (verify)

Primidone, sold under various brand names (including Mysoline), is a barbiturate medication that is used to treat partial and generalized seizures[7] and essential tremors.[8] It is taken by mouth.[7]

Its common side effects include sleepiness, poor coordination, nausea, and loss of appetite.[7] Severe side effects may include suicide and psychosis.[8][7] Use during pregnancy may result in harm to the fetus.[9] Primidone is an anticonvulsant of the barbiturate class;[7] however, its long-term effect in raising the seizure threshold is likely due to its active metabolite, phenobarbital.[10] The drug’s other active metabolite is phenylethylmalonamide (PEMA).

Primidone was approved for medical use in the United States in 1954.[7] It is available as a generic medication.[8] In 2020, it was the 269th most commonly prescribed medication in the United States, with more than 1 million prescriptions.[11][12]

  1. ^ "Primidone (Mysoline) Use During Pregnancy". Drugs.com. 18 February 2019. Archived from the original on 26 November 2020. Retrieved 16 May 2020.
  2. ^ Anvisa (31 March 2023). "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 4 April 2023). Archived from the original on 3 August 2023. Retrieved 16 August 2023.
  3. ^ "Primidone SERB 50mg Tablets - Summary of Product Characteristics (SmPC)". (emc). 18 August 2014. Archived from the original on 5 August 2019. Retrieved 16 May 2020.
  4. ^ a b c Ochoa JG, Riche W, Passaro EA (2005). Talavera F, Cavazos JE, Benbadis SR (eds.). "Antiepileptic Drugs: An Overview". eMedicine. eMedicine, Inc. Archived from the original on 8 February 2012. Retrieved 2 July 2005.
  5. ^ CDER, U.S. DEPARTMENT OF HEALTH AND HUMAN SERVICES (2003–2005). "Primidone (Mysoline)". Pharmacology Guide for Brain Injury Treatment. Brain Injury Resource Foundation. Archived from the original on 17 March 2010. Retrieved 2 July 2005.
  6. ^ Yale Medical School, Department of Laboratory Medicine (1998). "Therapeutic Drug Levels". YNHH Laboratory Manual - Reference Documents. Yale Medical School. Archived from the original on 20 February 2009. Retrieved 13 July 2005.
  7. ^ a b c d e f "Primidone Monograph for Professionals". Drugs.com. American Society of Health-System Pharmacists. Archived from the original on 29 June 2019. Retrieved 8 April 2019.
  8. ^ a b c British national formulary: BNF 76 (76 ed.). Pharmaceutical Press. 2018. p. 332. ISBN 9780857113382.
  9. ^ Cite error: The named reference birthdefects was invoked but never defined (see the help page).
  10. ^ Gilman AG, Goodman LS, Rall TW, Murad F, eds. (1985). Goodman and Gilman's The Pharmacological Basis of Therapeutics (7th ed.). New York: Macmillan.
  11. ^ "The Top 300 of 2020". ClinCalc. Archived from the original on 18 March 2020. Retrieved 7 October 2022.
  12. ^ "Primidone - Drug Usage Statistics". ClinCalc. Archived from the original on 11 April 2020. Retrieved 7 October 2022.