Small Acetaminophen Overdoses May Cause Liver Damage, Death: Study

A group of researchers are warning that consumers may be at risk of small, undetected acetaminophen overdoses that could lead to liver damage, liver failure or even death. 

A new study published last week in the British Journal of Clinical Pharmacology suggests that there could be a higher liver damage risk from so-called staggered overdoses, which are small overdoses that can occur over time, than from one large acetaminophen overdose.

According to researchers, small acetaminophen overdoses often go undetected and untreated in hospitals, where a large overdose, like from a suicide attempt, is much more easily detected, identified and treated.

Those small overdoses, caused by accidentally taking too much Tylenol or other drugs that contain the painkiller acetaminophen, can damage the liver over time, causing it to fail, which could lead to the need for a liver transplant and in some cases can cause death.

Researchers from the University of Edinburgh and the Scottish Liver Transplant Unit looked at medical data from 663 patients who suffered acetaminophen injuries from 1992 through 2008. They found that 161 suffered from staggered acetaminophen overdoses from trying to use Tylenol to treat common causes of pain, like headaches and muscle pain. Those patients were more likely to suffer from liver, kidney, breathing and brain problems, and had a higher risk of death than patients treated for large “one-off” acetaminophen overdoses.

One cause of the higher risk of problems was because the small, repeated acetaminophen overdoses were not as easily detectable via a blood test. This results in delayed treatment for acetaminophen liver damage, which increased the risk of death or the need for a liver transplant.

According to the FDA, acetaminophen overdose has been the leading cause of liver failure in the United States, resulting in more than 50,000 emergency room visits, 25,000 hospitalizations and over 450 deaths annually. Due to the risk of liver problems from Tylenol overdose, an FDA advisory panel was convened in June 2009 to make recommendations about new warnings or other regulatory actions.

In July 2011, in an effort to reduce the risk of liver damage from a Tylenol overdose, Johnson & Johnson agreed to lower the maximum recommended daily dose from 4,000mg to 3,000mg. Stronger warnings about the potential risk of liver failure have also been added to all acetaminophen products over the past year, including clearer indications about what products contain acetaminophen as the active ingredient to avoid the risk of overdose.

Although acetaminohen was first introduced more than 50 years ago, a growing number of people are now pursuing a Tylenol lawsuit after developing liver damage, raising similar allegations that Johnson & Johnson failed to adequately warn about the known risks associated with acetaminophen.