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ac·et·a·min·o·phen (APAP),

An antipyretic and analgesic, with potency similar to that of aspirin.
Synonym(s): paracetamol
Farlex Partner Medical Dictionary © Farlex 2012


(păr′ə-sē′tə-môl′, -môl′)
The American Heritage® Medical Dictionary Copyright © 2007, 2004 by Houghton Mifflin Company. Published by Houghton Mifflin Company. All rights reserved.


An over-the-counter analgesic used for headaches, muscle or joint pain, and fever, which lacks anti-inflammatory activity.
Therapeutic range
10–25 mg/L
Critical value
≥ 300 mg/L

Overdose can cause fatal liver failure. Up to 10% of hospitalisations for overdose and 40% of acute hepatic failure are linked to paracetamol overdose, which is more often accidental—e.g., children, alcoholics—than suicidal. Doses of > 150 mg/kg/24 hours cause acute liver failure.

Clinical stage of paracetamol toxicity
1. 1–24 hours—Non-specific.
2. 24–48 hours—Right upper quadrant pain, tenderness with elevated liver enzymes.
3. 72–96 hours—Marked increase in liver enzymes; fulminant hepatic failure, coagulopathy, acidosis.
4. 4–14 days—Liver recuperates or patient dies.

Pathogenesis of paracetamol overdose
90% is metabolised in the liver to non-toxic glucuronide and sulphate conjugates; 5% is oxidised by cytochrome p450 to NAPQI, which covalently binds to hepatocyte macromolecules, leading to hepatocyte death; 5% is excreted unchanged in urine.

Blood, urine.
Segen's Medical Dictionary. © 2012 Farlex, Inc. All rights reserved.


A drug widely used to relieve pain and reduce fever. The drug does not irritate the stomach, as ASPIRIN does, but overdose causes liver and kidney damage and may cause death from liver failure. 15 g or more is potentially serious. The victim remains well for a day or two and liver failure develops between the third and fifth day. The drug is on the WHO official list. Brand names are Alvedon, Calpol Disprol Paediatric, Infadrops, Medinol and Salzone. Preparations that include paracetamol include Cosalgesic, Distalgesic, Domperamol, Fortagesic, Kapake, Midrid, Migraleve, Paradote, Paramax, Remedeine and Solpadol.
Collins Dictionary of Medicine © Robert M. Youngson 2004, 2005
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The primary endpoint of this study was to compare the analgesic effects of intravenous dexketoprofen with those of paracetamol in combination with tramadol PCA during the first 24 hour following septoplasty.
At 7 pm on the second postoperative day, both groups showed better paracetamol analgesia effect in terms of better pain relief.
Last year, government figures revealed the NHS spends more than PS80m a year handing out paracetamol.
can't afford we need to paracetamol. as essential remedy.
Each sample in the calibration set contained two components (paracetamol, caffeine); each component was taken at five concentration levels (80, 90, 100, 110, and 120% reported to the theoretical amount).
A RP-HPLC method was improved for the simultaneous determination of Caffeine, Paracetamol and Orphenadrine citrate.
Rania Al Hashimi, a Jordanian visiting Dubai, said: "I have been in a habit of popping two pills of paracetamol on the first two days of Ramadan after Suhour for at least 15 years.
Se concluyo que la dosis de dos tabletas de ibuprofeno de 200 mg y paracetamol de 500 mg fue superior a las demas dosis estudiadas.
Unfortunately, many children like Mohammed had died because their mothers were only giving them paracetamol when they had fever.
Boots Calpol Infant Sugar Free Oral Suspension Strawberry Flavour 2+ Months 100ml 120mg/5ml paracetamol PS3.50 WILKO Healthpoint Children's Paracetamol Suspension 2M+ 100ml 120mg/5ml paracetamol PS1.20 Tesco Benylin Adult Tickly Cough Syrup 150ml 0.75ml glycerin PS5.25 WILKO Dry Tickly Cough Syrup 200ml 0.75ml glycerin PS1.80 LLOYDS Sudafed Congestion & Headache Relief 16s 500mg paracetamol, caffeine 25mg & phenylephrine hydrochloride 6.1mg PS4.09