PEBC: What You Need to Know: Acetaminophen

Indication: Fever and Pain

Dosing:

-Adults: every 4 to 6 hours; maximum 4000 mg per day for acute dosing; try to use less if chronic dosing

-Children: more accurate to use weight-based dosing: 10 to 15 mg/kg po every 4 to 6 hours, maximum 5 doses per day and 4000 mg per day

Adverse Effects:

-relatively well tolerated

-liver toxicity (in overdose, chronic use, combined with alcohol or hepatotoxic drugs)

-may treat liver toxicity with N-acetylcysteine

-remains drug of choice (compared to NSAIDs) in pregnant women for the shortest treatment period

Drug Interactions Causing Liver Toxicity:

-Alcohol and tyrosine kinase inhibitors (imatinib, dasatinib)

-CYP2E1 inducers (such as rifampin, isoniazid, phenytoin, carbamazepine, phenobarbital), which increase metabolism of acetaminophen into more hepatotoxic metabolites NAPQI