Aspirin: Medication used to treat pain and decrease the risk of heart disease

It is most commonly used as a pain killer, or to reduce fever or inflammation. It also has an anti-platelet effect - it reduces the number of platelets in the blood which reduces blood clotting- in that function it is used to prevent heart attacks. Aspirin is one of the most-used medical drugs in the world.

Aspirin
INN: acetylsalicylic acid

Clinical data
Pronunciation	acetylsalicylic acid /əˌsiːtəlˌsælɪˈsɪlɪk/
Trade names	Bayer Aspirin, many others
Synonyms	2-acetoxybenzoic acid acetylsalicylate acetylsalicylic acid O-acetylsalicylic acid, Aspirin (BAN UK), Aspirin (USAN US)
AHFS/Drugs.com	Monograph
MedlinePlus	a682878
License data	EU EMA: by INN US FDA: Aspirin
Pregnancy category	AU: C
Routes of administration	by mouth, rectal, lysine acetylsalicylate may be given intravenously or intramuscularly
ATC code	A01AD05 (WHO) B01AC06 (WHO), N02BA01 (WHO)
Legal status
Legal status	AU: S2 (Pharmacy medicine) except when given intravenously (in which case it is schedule 4), used in animal medicine (schedule 5/6) or when the dose is higher than usual. UK: General sales list (GSL, OTC) US: OTC
Pharmacokinetic data
Bioavailability	80–100%
Protein binding	80–90%
Metabolism	Liver, (CYP2C19 and possibly CYP3A), some is also hydrolysed to salicylate in the gut wall.
Elimination half-life	Dose-dependent; 2 h to 3 h for low doses (100 mg or less), 15 h to 30 h for large doses.
Excretion	Urine (80–100%), sweat, saliva, feces
Identifiers
IUPAC name 2-Acetoxybenzoic acid
CAS Number	50-78-2 Y
PubChem CID	2244
IUPHAR/BPS	4139
DrugBank	DB00945 Y
ChemSpider	2157 Y
UNII	R16CO5Y76E
KEGG	D00109 Y
ChEBI	CHEBI:15365 Y
ChEMBL	ChEMBL25 Y
PDB ligand	AIN (PDBe, RCSB PDB)
ECHA InfoCard	100.000.059
Chemical and physical data
Formula	C9H8O4
Molar mass	180.158 g/mol
3D model (JSmol)	Interactive image
Density	1.40 g/cm3
Melting point	136 °C (277 °F)
Boiling point	140 °C (284 °F) (decomposes)
Solubility in water	3 mg/mL (20 °C)
SMILES O=C(C)Oc1ccccc1C(=O)O
InChI InChI=1S/C9H8O4/c1-6(10)13-8-5-3-2-4-7(8)9(11)12/h2-5H,1H3,(H,11,12) Y Key:BSYNRYMUTXBXSQ-UHFFFAOYSA-N Y
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There are some possible side-effects to this drug. For example, large amounts can damage the kidneys. Children taking aspirin can develop Reye's syndrome which causes the liver to become fatty and not work properly and also the brain to become enlarged. Reyes syndrome can be fatal, but most children survive it with treatment.

People with lung, kidney disease, gout, hyperuricemia (high amounts of uric acid in the blood), hemophilia (a blood clotting disorder), diabetes or high blood pressure should not take aspirin except on the advice of a qualified medical professional. Nor should people who are allergic to it, to ibuprofen or to naproxen. People with asthma where attacks are brought about by aspirin should avoid using any anti-inflammatory drugs based on it.

Aspirin was invented in Germany in 1897. Bayer has a trademark on the brand name "aspirin" in 80 countries. But in other countries, "aspirin" is the common name for the drug.