Acetaminophen Poisoning

ByGerald F. O’Malley, DO, Grand Strand Regional Medical Center;
Rika O’Malley, MD, Grand Strand Medical Center
Reviewed/Revised May 2022 | Modified Sept 2022
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(See also Overview of Poisoning.)

Liver failure can follow.

Most overdoses cause no immediate symptoms. If the overdose is very large, symptoms develop in 4 stages:

  • In stage 1 (after several hours), the person may vomit but does not seem ill. Many people have no symptoms in stage 1.

  • In stage 2 (after 24 to 72 hours), nausea, vomiting, and abdominal pain may develop. At this stage, blood tests show that the liver is functioning abnormally.

  • In stage 3 (after 3 to 4 days), vomiting becomes worse. Tests show that the liver is functioning poorly, and jaundice (yellowing of the eyes and skin) and bleeding develop. Sometimes the kidneys fail and the pancreas becomes inflamed (pancreatitis).

  • In stage 4 (after 5 days), the person either recovers or experiences failure of the liver and often other organs, which may be fatal.

If toxicity results from multiple smaller doses taken over time, the first indication of the problem may be abnormal liver function, sometimes with jaundice and/or bleeding.

  • Abnormal liver function tests

suicide

  • Sometimes, treatment for liver failure or liver transplant

Treatment for liver failure or liver transplant may also be necessary.

More Information

The following is an English-language resource that may be useful. Please note that THE MANUAL is not responsible for the content of this resource.

  1. American Association of Poison Control Centers: Represents the US-based poison centers that provide free, confidential services (24/7) through the Poison Help Line (1-800-222-1222)

Drugs Mentioned In This Article
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