| To obtain emergency consultation with a medical toxicologist, in the United States, call 1-800-222-1222, or the nearest international regional poison center. Contact information for regional poison centers around the world is available at the website referenced below.[1] |
| Clinical presentation |
| Nausea and vomiting are common early symptoms |
| Patients that subsequently develop hepatic injury and death may be asymptomatic for HOURS after an acute ingestion |
| Diagnostic evaluation |
| In all patients with suspected acetaminophen (APAP) toxicity, obtain the following: serum acetaminophen concentration, baseline liver function tests (AST, ALT, total bilirubin), PT and INR, and basic chemistry panel (electrolytes, BUN, creatinine) |
| In all patients with a suspected intentional overdose, obtain serum salicylate concentration, fingerstick glucose, ECG, and qualitative pregnancy test in women of childbearing age |
| Treatment |
| Secure airway, breathing, and circulation as necessary |
| Give activated charcoal (AC) 50 g to all adult patients presenting within 4 hours of ingestion, unless contraindicated; AC may be useful for coingestants beyond 4 hours |
| Treat with N-acetylcysteine (NAC) if: |
| Serum APAP concentration drawn at 4 hours or more after a single acute ingestion is above the "treatment" line of the treatment nomogram for APAP poisoning |
| Serum APAP concentration is unavailable or will not return within 8 hours of time of ingestion and APAP ingestion is suspected |
| Time of ingestion is unknown and serum APAP level is greater than 10 mcg/mL (66 µmol/L) |
| There is evidence of ANY hepatotoxicity with a history of APAP ingestion |
| Patient reports or clinician suspects repeated excessive APAP ingestions, patient has risk factors for APAP-induced hepatotoxicity, and the serum APAP concentration is greater than 10 mcg/mL (66 µmol/L) |
| Oral dosing of NAC: |
| Oral dosing is acceptable for non-pregnant patients with a functional GI tract and no evidence of hepatotoxicity |
| Dose 140 mg/kg loading dose, followed by 17 doses of 70 mg/kg every 4 hours |
| If vomiting occurs within 1 hour of NAC dosing, a full NAC dose should be repeated as rapidly as possible |
| Therapy may be terminated by 24 to 36 hours after ingestion if the acetaminophen level is below 10 micrograms/mL, and the patient does not develop evidence of hepatotoxicity and remains clinically well |
| Intravenous (IV) dosing of NAC: |
| In patients with no biochemical evidence of hepatic failure (ie, those with INR <2), use 21 hour IV protocol: 150 mg/kg loading dose over 60 minutes, followed by 50 mg/kg infused over 4 hours, with the final 100 mg/kg infused over the remaining 16 hours |
| In patients with biochemical evidence of hepatic failure (ie, those with INR >2), administer the 21 hour IV protocol (150 mg/kg loading dose over 60 minutes, followed by 50 mg/kg infused over 4 hours, followed by 100 mg/kg infused over the next 16 hours) followed by a continuous IV NAC infusion at 6.25 mg/kg per hour until INR is <2 |
| IV dosing is acceptable in all cases of acetaminophen toxicity, but should be used INSTEAD of oral dosing in patients unable to tolerate oral NAC (eg, intractable vomiting), patients with a medical condition precluding administration of oral NAC (eg, corrosive ingestion, GI bleed), patients with significant hepatotoxicity (INR >2), and pregnant patients |
| Antiemetic therapy: |
| May give 5-HT3 receptor antagonist (eg, ondansetron) or metoclopramide |
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