Chemical Component Summary

NameN-(4-HYDROXYPHENYL)ACETAMIDE (TYLENOL)
IdentifiersN-(4-hydroxyphenyl)ethanamide
FormulaC8 H9 N O2
Molecular Weight151.16
TypeNON-POLYMER
Isomeric SMILESCC(=O)Nc1ccc(O)cc1
InChIInChI=1S/C8H9NO2/c1-6(10)9-7-2-4-8(11)5-3-7/h2-5,11H,1H3,(H,9,10)
InChIKeyRZVAJINKPMORJF-UHFFFAOYSA-N

Chemical Details

Formal Charge0
Atom Count20
Chiral Atom Count0
Chiral Atomsn/a
Bond Count20
Aromatic Bond Count6
Leaving Atomsn/a

Drug Info: DrugBank

DrugBank IDDB00316 Different stereochemistry
NameAcetaminophen
Groupsapproved
DescriptionAcetaminophen, also known as paracetamol, is commonly used for its analgesic and antipyretic effects. Its therapeutic effects are similar to salicylates, but it lacks anti-inflammatory, antiplatelet, and gastric ulcerative effects.
Synonyms
  • 4-(Acetylamino)phenol
  • 4-acetamidophenol
  • 4'-hydroxyacetanilide
  • Acenol
  • acetaminofén
Brand Names
  • (extra Strength) Acetaminophen, Caffeine & 8mg Codeine Phosphate Caplets
  • 10 Person Ansi
  • 222 AF Extra
Affected OrganismHumans and other mammals
IndicationFor temporary relief of fever, minor aches, and pains.
PharmacologyAcetaminophen (USAN) or Paracetamol (INN) is a widely used analgesic and antipyretic drug that is used for the relief of fever, headaches, and other minor aches and pains. It is a major ingredient in numerous cold and flu medications and many prescription analgesics. It is extremely safe in standard doses, but because of its wide availability, deliberate or accidental overdoses are not uncommon. Acetaminophen, unlike other common analgesics such as aspirin and ibuprofen, has no anti-inflammatory properties or effects on platelet function, and it is not a member of the class of drugs known as non-steroidal anti-inflammatory drugs or NSAIDs. At therapeutic doses acetaminophen does not irritate the lining of the stomach nor affect blood coagulation, kidney function, or the fetal ductus arteriosus (as NSAIDs can). Like NSAIDs and unlike opioid analgesics, acetaminophen does not cause euphoria or alter mood in any way. Acetaminophen and NSAIDs have the benefit of being completely free of problems with addiction, dependence, tolerance and withdrawal. Acetaminophen is used on its own or in combination with pseudoephedrine, dextromethorphan, chlorpheniramine, diphenhydramine, doxylamine, codeine, hydrocodone, or oxycodone.
Mechanism of actionAcetaminophen is thought to act primarily in the CNS, increasing the pain threshold by inhibiting both isoforms of cyclooxygenase, COX-1, COX-2, and COX-3 enzymes involved in prostaglandin (PG) synthesis. Unlike NSAIDs, acetaminophen does not inhibit cyclooxygenase in peripheral tissues and, thus, has no peripheral anti-inflammatory affects. While aspirin acts as an irreversible inhibitor of COX and directly blocks the enzyme's active site, studies have found that acetaminophen indirectly blocks COX, and that this blockade is ineffective in the presence of peroxides. This might explain why acetaminophen is effective in the central nervous system and in endothelial cells but not in platelets and immune cells which have high levels of peroxides. Studies also report data suggesting that acetaminophen selectively blocks a variant of the COX enzyme that is different from the known variants COX-1 and COX-2. This enzyme is now referred to as COX-3. Its exact mechanism of action is still poorly understood, but future research may provide further insight into how it works. The antipyretic properties of acetaminophen are likely due to direct effects on the heat-regulating centres of the hypothalamus resulting in peripheral vasodilation, sweating and hence heat dissipation.
Route of administration
  • Intravenous
  • Oral
  • Oral; Topical
  • Rectal
  • Topical
Categories
  • Acetanilides
  • Acetates
  • Acids, Acyclic
  • Amides
  • Analgesics
ATC-Code
  • N02BE01
  • N02BE51
  • N02BE71
AHFS-Code28:08.92
CAS number103-90-2
Drug Info/Drug Targets: DrugBank 3.0: a comprehensive resource for 'omics' research on drugs. Knox C, Law V, Jewison T, Liu P, Ly S, Frolkis A, Pon A, Banco K, Mak C, Neveu V, Djoumbou Y, Eisner R, Guo AC, Wishart DS. Nucleic Acids Res. 2011 Jan; 39 (Database issue):D1035-41. | PMID:21059682