TOXICOLOGY
TREATMENT
■ Supportive therapy as indicated.
■ Activated charcoal: If <4 hours (2 hours per recent study) from time of
ingestion
■ Antidote: N-acetylcysteine (NAC)
■ Very effective if given within 8 hoursof ingestion, but even late admin-
istration is beneficial (alwaysgive NAC).
■ If no acetaminophen level available and patient approaching (or
exceeding) 8 hours from ingestion →give NAC.
■ Oral dose (Mucomyst): 140 mg/kg load, then 70 mg/kg every 4 hours.
■ Intravenous (Acetadote) administration is indicated for fulminant
hepatic failure, intractable vomiting, or pregnancy.
■ May cause dose-, rate-, and concentration-dependent anaphylactoid
reactions
Possible
Toxicity
Toxicity
Unlikely
Take levelat least
4 hourspost-ingestion
FIGURE 6.2. Rumack-Matthew nomogram. Serum acetaminophen concentration vs
time after acute ingestion.
(Reproduced, with permission, from Rumack BH, Matthew H. Acetaminophen poisoning and
toxicity. Pediatrics55:871, 1975.)
NAC is most effective if given
within 8 hours of
ingestion.
Even late administration of
NAC can be beneficial.
Acetaminophen toxicity:
Toxic single dose = 150 mg/kg
(about 7.5 g for adults)
Toxic level at 4 hours =
150 mcg/mL
Oral NAC loading dose =
140 mg/kg