ConceptQ57055· pop 105· linked from 1,573 articles

Paracetamol

Also known as p-acetylaminophenol, acetaminofen4-(acetylamino)phenol, N-acetyl-p-aminophenol4-hydroxyacetanilide, N-(4-hydroxyphenyl)acetamide, p-hydroxyacetanilide, p-acetaminophenol, p-acetamidophenol, 4'-hydroxyacetanilide

Paracetamol, or acetaminophen, is an analgesic and antipyretic agent used to treat fever and mild to moderate pain. It is a widely available over-the-counter drug sold generically or under various brand names, including Tylenol and Panadol.

OverviewAI-generated

Paracetamol, also known as acetaminophen, is a small molecule with the chemical formula C₈H₉NO₂ and a molecular weight of approximately 151. It serves as an antipyretic and essential medicine, with its international non-proprietary name designated by the World Health Organisation. The substance is the active ingredient in Tylenol and has been approved since 1968. It is used to treat conditions including fever, pain, hyperthermia, nasopharyngitis, osteoarthritis, and arthritis.

The drug can be administered orally, rectally, via intravenous infusion or injection, intramuscularly, or topically. It physically interacts with Prostaglandin-endoperoxide synthase 1 and 2. Significant drug interactions include isoniazid, rifampicin, rifabutin, and phenytoin. Paracetamol exhibits bitterness, a crystal structure, and combustibility, with a melting point of 170 and a density of 1.293. It carries a boxed warning and is subject to Regulation (EC) No. 1272/2008.

Synthesized by Vinony from 43 facts across 5 sources: Wikidata, PubChem, PubMed, ChEMBL, Vinony graph. Generated from structured data (not the Wikipedia text) and checked against those facts — may still contain errors.

Wikipedia views (30d)

82,680 total

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Key facts

Drug.image: Paracetamol-skeletal.svg
Drug.image_class: skin-invert-image
Drug.width: 210
Drug.imageL: Paracetamol-from-xtal-3D-balls.png
Drug.image_classL: bg-transparent
Drug.imageR: Paracetamol-from-xtal-3D-vdW.png
Drug.image_classR: bg-transparent
Drug.USAN: acetaminophen
Drug.pronounce: Paracetamol: Acetaminophen:
Drug.tradename: Tylenol, Panadol, others
Drug.MedlinePlus: a681004
Drug.DailyMedID: Acetaminophen
Drug.pregnancy_AU: A
Drug.routes_of_administration: By mouth, intravenous, rectal
Drug.ATC_prefix: N02
Drug.ATC_suffix: BE01
Drug.legal_AU: S4
Drug.legal_AU_comment: OTC, and unscheduled

via Wikipedia infobox

Chemical data

Formula: C8H9NO2
Molecular weight: 151.16 g/mol
IUPAC name: N-(4-hydroxyphenyl)acetamide
SMILES: CC(=O)NC1=CC=C(C=C1)O
InChIKey: RZVAJINKPMORJF-UHFFFAOYSA-N
XLogP: 0.5
Polar surface area: 49.3 Å²
H-bond donors: 2
H-bond acceptors: 2
Formal charge: 0

via PubChem

Drug data · ChEMBL

Max clinical phase: Approved
Molecule type: Small molecule
First approval: 1968
Admin. routes: oral, parenteral, topical
Indications: Fever, osteoarthritis, knee, pain, arthritis

via ChEMBL · EBI

Research

38,408 papers

Paracetamol (Acetaminophen) and the Developing Brain.ReviewInternational journal of molecular sciences · 2021Bührer C, Endesfelder S, Scheuer T et al.DOI: 10.3390/ijms222011156
Kinetics and metabolism of paracetamol and phenacetin.ReviewBritish journal of clinical pharmacology · 1980Prescott LFDOI: 10.1111/j.1365-2125.1980.tb01812.x
Mechanism of action of paracetamol.ReviewAmerican journal of therapeutics · 2005Graham GG, Scott KFDOI: 10.1097/00045391-200501000-00008
Paracetamol (acetaminophen) poisoning: The early years.ReviewBritish journal of clinical pharmacology · 2024Prescott LFDOI: 10.1111/bcp.15903
Interventions for paracetamol (acetaminophen) overdose.The Cochrane database of systematic reviews · 2018Chiew AL, Gluud C, Brok J et al.DOI: 10.1002/14651858.CD003328.pub3
Paracetamol: new vistas of an old drug.ReviewCNS drug reviews · 2006Bertolini A, Ferrari A, Ottani A et al.DOI: 10.1111/j.1527-3458.2006.00250.x
Acetaminophen/paracetamol: A history of errors, failures and false decisions.ReviewEuropean journal of pain (London, England) · 2015Brune K, Renner B, Tiegs GDOI: 10.1002/ejp.621
Paracetamol: the potential therapeutic pathways defining its clinical use.ReviewInflammopharmacology · 2025Al-Kuraishy HM, Al-Gareeb AI, Albuhadily AK et al.DOI: 10.1007/s10787-025-01779-x

via PubMed

Wikidata facts

Subclass of: phenols
Mass: 151.063
Image: Paracetamol substance photo.jpg
Autonomy: 540
Has use: medication

Show 23 more facts

Commons category: Paracetamol
chemical formula: C₈H₉NO₂
significant drug interaction: acenocoumarol
route of administration: intramuscular injection
World Health Organisation international non-proprietary name: paracetamol
medical condition treated: fever
canonical SMILES: CC(=O)NC1=CC=C(C=C1)O
legal status (medicine): boxed warning
subject has role: essential medicine
melting point: 168
WordLift URL: data.medicalrecords.com/medicalrecords/healthwise/acetaminophen
density: 1.293
partition coefficient water/octanol: 0.46
median lethal dose (LD50): 1940
safety classification and labelling: Regulation (EC) No. 1272/2008
has characteristic: combustibility
has effect: paracetamol toxicity
color: white
associated hazard: dust explosion
pH value: 6
median lethal concentration (LC50): 814
half maximal effective concentration (EC50): 9.2
does not have effect: autism

Sources (10)

via Wikidata · CC0

~35 min read

Encyclopedic overview

33 sections

Contents

Medical uses
Fever
Pain
Musculoskeletal pain
Headaches
Dental and other post-surgical pain
Other pain
Patent ductus arteriosus
Use in pregnancy and breastfeeding
Pregnancy
Breastfeeding
Adverse effects
Overdose
Interactions
Pharmacology
Pharmacodynamics
Pharmacokinetics
Chemistry
Synthesis
Classical methods
Celanese synthesis
Reactions
History
Society and culture
Naming
Available forms
Veterinary use
Cats
Dogs
Snakes
Notes
References
External links

Paracetamol relieves pain in both acute mild migraine and episodic tension headache. At a standard dose, paracetamol slightly reduces fever, though it is inferior to ibuprofen in that respect and the benefits of its use for fever are unclear, particularly in the context of fever of viral origins. The aspirin/paracetamol/caffeine combination also helps with both conditions when the pain is mild and is recommended as a first-line treatment for them. Paracetamol is effective for pain after wisdom tooth extraction, but it is less effective than ibuprofen. The combination of paracetamol and ibuprofen provides greater analgesic efficacy than either drug alone. The pain relief paracetamol provides in osteoarthritis is small and clinically insignificant. Evidence supporting its use in low back pain, cancer pain, and neuropathic pain is insufficient. Paracetamol is the first-line treatment for pain and fever in pregnancy; no causal association with neurodevelopmental disorders has been established, while untreated pain and fever can harm the mother and fetus.

Excerpted from Wikipedia’s “Paracetamol” article, available under the CC BY-SA 4.0 licence.