A Review on Paracetamol: Pharmacology, Uses and Toxicity
DOI:
https://doi.org/10.15662/IJRAI.2026.0903010Keywords:
Paracetamol, Acetaminophen, Analgesic, Antipyretic, Pharmacology, Pain management, Fever, Hepatotoxicity, NAPQI, Glutathione, Overdose, Liver failure, N-acetylcysteine, NSAIDs, Drug safety, Therapeutic uses, Dosage, Toxicity, Pharmacokinetics, Mechanism of action, Drug metabolism, Clinical practice, Patient safety, OTC medicineAbstract
One of the most widely used analgesic and antipyretic medications used in the management of pain and fever worldwide is Paracetamol (acetaminophen). Its efficacy, low cost, broad availability and relatively good safety profile when used within its recommended dosage makes it a first-line therapeutic option since its introduction into clinical practice. Contrary to non-steroidal anti-inflammatory drugs (NSAIDs), paracetamol is an effective agent of mild to moderate pain relief, fever reduction, and none of the drugs has significant side effects on the gastrointestinal tract, platelets, or cardiovascular systems. This is particularly helpful when used with children, elderly patients, pregnant women due to medical supervision, and patients in whom NSAIDs are contraindicated. Pharmacologically, paracetamol acts primarily in the central nervous system by inhibiting the synthesis of prostaglandins hence giving it analgesic and antipyretic properties. It has little anti-inflammatory effect due to its low peripheral cyclooxygenase inhibition. Paracetamol is readily absorbed after oral administration, widely distributed and mainly metabolised in the liver by glucuronidation and sulfation pathways. Cytochrome P450 enzymes are able to convert a small proportion to a toxic metabolite, N-acetyl-p-benzoquinone imine (NAPQI), which would otherwise be detoxified by glutathione. But when glutathione stores are depleted (either in overdose or in prolonged excessive use) glutathione accumulates in the body, leading to severe hepatocellular injury. One of the most common causes of acute liver failure in world and may occur as either an intentional overdose of paracetamol, a repeated high-dose of paracetamol or as an accidental ingestion of multiple combination products containing paracetamol. Serum drug level and treatment with N-acetylcysteine (NAC) is the key to preventing serious complications. This review discusses the pharmacology, mechanism of action, therapeutic uses, dosage, administration, toxicity, and management of paracetamol. It also notes major advantages of it like safety, accessibility, and tolerability, and major limitations of it such as hepatotoxicity and important lack of anti-inflammatory effects. Rational prescribing, patient education, and close monitoring are all fundamental in maximizing therapeutic benefits, and minimizing the risks associated with the use of this widespread drug.References
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