Also Known As: Paracetamol, Sedapap, Wygesic, Tylenol, Acetaminophen
Paracetamol INN, or acetaminophen is a widely used over-the-counter analgesic (pain reliever) and antipyretic (fever reducer). It is commonly used for the relief of headaches and other minor aches and pains and is a major ingredient in numerous cold and flu remedies. In combination with opioid analgesics, paracetamol can also be used in the management of more severe pain such as post-surgical pain and providing palliative care in advanced cancer patients. The onset of analgesia is approximately 11 minutes after oral administration of paracetamol, and its half-life is 1â€“4 hours.
While generally safe for use at recommended doses (1,000 mg per single dose and up to 3,000 mg per day for adults), acute overdoses of paracetamol can cause potentially fatal liver damage and, in rare individuals, a normal dose can do the same; the risk is heightened by alcohol consumption. Paracetamol toxicity is the foremost cause of acute liver failure in the Western world, and accounts for most drug overdoses in the United States, the United Kingdom, Australia and New Zealand.
It is the active metabolite of phenacetin, once popular as an analgesic and antipyretic in its own right, but unlike phenacetin and its combinations, paracetamol is not considered carcinogenic at therapeutic doses. The words acetaminophen (used in the United States, Canada, Japan, South Korea, Hong Kong, and Iran) and paracetamol (used elsewhere) both come from a chemical name for the compound: para-acetylaminophenol and para-acetylaminophenol. In some contexts, it is simply abbreviated as APAP, for acetyl-para-aminophenol.
Paracetamol is approved for reducing fever in people of all ages. The World Health Organization (WHO) recommends that paracetamol only be used to treat fever in children if their temperature is greater than 38.5 °C (101.3 °F). The efficacy of paracetamol by itself in children with fevers has been questioned and a meta-analysis showed that it is less effective than ibuprofen. Paracetamol has a well-established role in pediatric medicine as an effective analgesic and antipyretic.
Paracetamol is used for the relief of pains associated with many parts of the body. It has analgesic properties comparable to those of aspirin, while its anti-inflammatory effects are weaker. It is better tolerated than aspirin in patients in whom excessive gastric acid secretion or prolongation of bleeding time may be a concern. Available without a prescription, it has in recent years increasingly become a common household drug.
Paracetamol can relieve pain in mild arthritis but has no effect on the underlying inflammation, redness, and swelling of the joint. It is as effective as the non-steroidal anti-inflammatory drug ibuprofen in relieving the pain of osteoarthritis of the knee.
Paracetamol has relatively little anti-inflammatory activity, unlike other common analgesics such as the NSAIDs aspirin and ibuprofen.
Regarding comparative efficacy, studies show conflicting results when compared to NSAIDs. A randomized controlled trial of chronic pain from osteoarthritis in adults found similar benefit from paracetamol and ibuprofen.
The efficacy of paracetamol when used in a combination form with weak opioids (such as codeine) has been questioned by recent data studies; the small amount of data available have made reaching a conclusion difficult. Combination drugs of paracetamol and strong opioids like morphine have been shown to reduce the amount of opioid used and improve analgesic effect as well as discouraging overuse of addictive opioids due to APAP's potentially toxic effects.
A randomized controlled trial of acute musculoskeletal pain in children found that the standard over-the-counter dose of ibuprofen gives greater pain relief than the standard dose of paracetamol.