Paracetamol
| Category | Biochemistry |
|---|---|
| Test background |
Paracetamol (acetominophen) is an analgesic, antipyretic drug lacking significant anti-inflammatory activity. It is metabolised by the liver with a normal elimination half-life of <4 hours. In normal therapeutic doses, a minor metabolite readily reacts with glutathione in the liver to yield a detoxified product. In overdose situations, liver glutathione is consumed and the toxic metabolite (postulated metabolite: benzoquinone) reacts with cellular proteins resulting in hepatotoxicity and possible death if untreated. N-acetylcysteine can substitute for glutathione and serves as an antidote. |
| Clinical Indications |
Suspected overdose: symptoms include nausea and vomiting, right subcostal pain and tenderness (hepatic necrosis). |
| Reference range | See British National Formulary for overdose guidelines |
| Sample & container required | SST (gold top) |
| Sample volume | 0.5 mL |
| Turnaround time | 1 day |