Acetaminophen

Norm    
Therapeutic concentration 66–199µmol/l
Toxic concentration    
4 hours after the last dose more than 993µmol/l
12 hours after the last dose more than 496µmol/l
24 hours after the last dose more than 265µmol/l

Synonyms: Tylenol, Acetaminophen, Paracetamol” and others
Serum
Red cap

Acetaminophen (paracetamol) is one of the most commonly used drugs when a rapid antipyretic and analgesic effect is needed. Acetaminophen may be recommended for children as aspirin can cause Reye’s syndrome. Due to the relatively narrow therapeutic range, determining the drug concentration in the blood is very important. Signs of acetaminophen toxicity may appear late, 24-48 hours after oral ingestion of a regular dose. Toxicity manifests earliest in the liver. Additional laboratory tests in case of suspected intoxication: AST, ALT, GGT, bilirubin, urea, creatinine, glucose, PTT. Antidote – Mucomyst^® (acetylcysteine).

Source | Handbook of Basic Laboratory Tests | Doctor of Medical Sciences Gintaras Zaleskis