Timolol

Timolol
Clinical data
Trade names	Timoptic, others
AHFS/Drugs.com	Maleate Monograph; eent Monograph
MedlinePlus	a684029
License data	US DailyMed: Timolol;
Pregnancy; category	AU: C;
Routes of; administration	By mouth, topical (eye drop)
Drug class	Beta blocker
ATC code	C07AA06 (WHO) S01ED01 (WHO) C07BA06 (WHO) C07DA06 (WHO); Combination: S01ED51 (WHO);
Legal status
Legal status	CA: ℞-only; UK: POM (Prescription only); US: ℞-only;
Pharmacokinetic data
Bioavailability	60%
Metabolism	Liver (80%, mainly CYP2D6)
Onset of action	15–30 min
Elimination half-life	2.5–5 hours
Duration of action	24 hours
Excretion	Kidney
Identifiers
	IUPAC name (S)-1-(tert-Butylamino)-3-[(4-morpholin-4-yl-1,2,5-thiadiazol-3-yl)oxy]propan-2-ol;
CAS Number	26839-75-8 ;
PubChem CID	33624;
IUPHAR/BPS	565;
DrugBank	DB00373 ;
ChemSpider	31013 ;
UNII	5JKY92S7BR;
KEGG	D08600 ; as salt: D00603 ;
ChEBI	CHEBI:9599 ;
ChEMBL	ChEMBL499 ;
CompTox Dashboard (EPA)	DTXSID4023674 ;
ECHA InfoCard	100.043.651
Chemical and physical data
Formula	C13H24N4O3S
Molar mass	316.42 g·mol−1
3D model (JSmol)	Interactive image;
	SMILES CC(C)(C)NCC(O)COc1nsnc1N1CCOCC1;
	InChI 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 ; Key:BLJRIMJGRPQVNF-JTQLQIEISA-N ;
	(verify)

Timolol is a beta blocker medication used either by mouth or as eye drops. As eye drops it is used to treat increased pressure inside the eye such as in ocular hypertension and glaucoma. 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.

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

Timolol was patented in 1968, and came into medical use in 1978. It is on the World Health Organization's List of Essential Medicines. Timolol is available as a generic medication. In 2022, it was the 155th most commonly prescribed medication in the United States, with more than 3 million prescriptions.