Timolol

Timolol
Clinical data
Trade namesBetimol, Blocadren, Istalol, Timoptic, others[1]
AHFS/Drugs.comMaleate Monograph
eent Monograph
MedlinePlusa684029
License data
Pregnancy
category
  • AU: C
Routes of
administration		By mouth, topical (eye drop)
Drug classBeta blocker
ATC code
Legal status
Legal status
Pharmacokinetic data
Bioavailability60%
MetabolismLiver (80%, mainly CYP2D6[4])
Onset of action15–30 min[3]
Elimination half-life2.5–5 hours
Duration of action24 hours[3]
ExcretionKidney
Identifiers
  • (S)-1-(tert-Butylamino)-3-[(4-morpholin-4-yl-1,2,5-thiadiazol-3-yl)oxy]propan-2-ol
CAS Number
PubChem CID
IUPHAR/BPS
DrugBank
ChemSpider
UNII
KEGG
ChEBI
ChEMBL
CompTox Dashboard (EPA)
ECHA InfoCard100.043.651 Edit this at Wikidata
Chemical and physical data
FormulaC13H24N4O3S
Molar mass316.42 g·mol−1
3D model (JSmol)
  • CC(C)(C)NCC(O)COc1nsnc1N1CCOCC1
  • InChI=1S/C13H24N4O3S/c1-13(2,3)14-8-10(18)9-20-12-11(15-21-16-12)17-4-6-19-7-5-17/h10,14,18H,4-9H2,1-3H3/t10-/m0/s1 checkY
  • Key:BLJRIMJGRPQVNF-JTQLQIEISA-N checkY
  (verify)

Timolol is a beta blocker medication used either by mouth or as eye drops.[3][5] As eye drops it is used to treat increased pressure inside the eye such as in ocular hypertension and glaucoma.[3] By mouth it is used for high blood pressure, chest pain due to insufficient blood flow to the heart, to prevent further complications after a heart attack, and to prevent migraines.[5]

Common side effects with the drops is irritation of the eye.[3] Common side effects by mouth include tiredness, slow heart beat, itchiness, and shortness of breath.[5] Other side effects include masking the symptoms of low blood sugar in those with diabetes.[3] Use is not recommended in those with asthma, uncompensated heart failure, or COPD.[3] It is unclear if use during pregnancy is safe for the fetus.[6] Timolol is a non-selective beta blocker.[3]

Timolol was patented in 1968, and came into medical use in 1978.[7] It is on the World Health Organization's List of Essential Medicines.[8] Timolol is available as a generic medication.[3][9] In 2021, it was the 163rd most commonly prescribed medication in the United States, with more than 3 million prescriptions.[10][11]

  1. ^ Cite error: The named reference genericnames was invoked but never defined (see the help page).
  2. ^ "Product monograph brand safety updates". Health Canada. February 2024. Retrieved 24 March 2024.
  3. ^ a b c d e f g h i "Timolol eent". The American Society of Health-System Pharmacists. Archived from the original on 28 December 2016. Retrieved 8 December 2016.
  4. ^ Volotinen M, Turpeinen M, Tolonen A, Uusitalo J, Mäenpää J, Pelkonen O (July 2007). "Timolol metabolism in human liver microsomes is mediated principally by CYP2D6". Drug Metabolism and Disposition. 35 (7): 1135–1141. doi:10.1124/dmd.106.012906. PMID 17431033. S2CID 794764.
  5. ^ a b c "Timolol Maleate". The American Society of Health-System Pharmacists. Archived from the original on 28 December 2016. Retrieved 8 December 2016.
  6. ^ "Timolol ophthalmic Use During Pregnancy". The American Society of Health-System Pharmacists. Archived from the original on 28 December 2016. Retrieved 28 December 2016.
  7. ^ Fischer J, Ganellin CR (2006). Analogue-based Drug Discovery. John Wiley & Sons. p. 460. ISBN 9783527607495. Archived from the original on 28 December 2016.
  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. ^ "Competitive Generic Therapy Approvals". U.S. Food and Drug Administration (FDA). 29 June 2023. Archived from the original on 29 June 2023. Retrieved 29 June 2023.
  10. ^ "The Top 300 of 2021". ClinCalc. Archived from the original on 15 January 2024. Retrieved 14 January 2024.
  11. ^ "Timolol - Drug Usage Statistics". ClinCalc. Retrieved 14 January 2024.