Acetaminophen Poisoning

Question 1

What are the subjective / physical findings associated with acetaminophen toxicity?

Answer 1

• Subjective: usually asymptomatic early despite ingestion of toxic amounts; N/V at 24-48 hours, RUQ pain, hypotension, hypothermia
• Physical findings: Jaundice, prolonged bleeding times, hepatic encephalopathy symptoms. Patients can develop fulmanint hepatic failure, cerebral edema and sepsis.

Question 2

What are some lab findings associated with acetaminophen toxicity?

Answer 2

• Toxicity and liver injury seen with high doses.
• Higher risk for hepatic injury in patients with alcohol abuse, those with prior liver disease
• Monitor every 24 hours: Elevated aspartate transaminase, alanine transaminase, BUN, creatinine, PT, bilirubin. Monitor for metabolic acidosis
• Test for potential concurrent overdose with opioids/drugs of abuse

Question 3

How do you manage patients with acetaminophen toxicity?

Answer 3

• Activated charcoal 25-100 grams diluted in water IF the patient presents within 4 hours of ingestion. If acetylcysteine is also to be administered, charcoal should be removed by gastric lavage as this may prevent absorption
• N-Acetylcysteine (Mucomyst): 140 mg/kg loading dose given within 8-10 hours of overdose. Followed by maintenance doses of 70 mg/kg every 4 hours for total of 17 doses if the acetaminophen level remains toxic (above 20 mcg/ml). Check blood levels every 4 hours to be sure.
• Acetylcysteine may also be given in the IV form of Acetadote in D5W in 3 doses. Monitor the patient for allergic reactions. The 3 doses are as follows: 150 mg/kg, 50 mg/kg, 100 mg/kg.