The FDA has reported that doses of Tylenol (acetaminophen) as low as 2.5-grams per day can cause liver injury. The maximum daily dose is limited to 3-grams per day (about 6 Extra-Strength Tylenol), which was reduced from 4-grams per day to reduce the risk of overdose.
What Dose of Tylenol Is Safe?
The “safe” dose of Tylenol (acetaminophen) is different for everyone. Most healthy adults can tolerate up to 3,000-mg per day (about 6 Extra-Strength Tylenol with 500-mg per pill) before they suffer liver injury or acute liver failure. However, some people have higher risks of overdoses than others — especially people who drink alcohol or have pre-existing liver problems.
How Do Tylenol Overdoses Occur?
Overdoses occur any time the liver cannot safely metabolize all of the Tylenol a person consumes. When this happens, the liver creates a toxic metabolite that destroys cells in the liver and causes necrosis (tissue death). People who have problems clearing this metabolite or producing too much of the metabolite are more likely to have an overdose.
Acetaminophen Overdose Amount
Talk to your doctor about all of the medications you are taking and the “safe” dose of acetaminophen. More than 600 medications contain acetaminophen and it is easy to overdose when more than one of these medications are combined.
The lowest known acetaminophen overdose amount in a healthy adult is 2.5-grams per day, according to this report published by the U.S. Food and Drug Administration in 2009.
However, according to this study published by the Journal of Clinical Gastroenterology in 2009, “The threshold dose to cause hepatotoxicity is 10 to 15 g of acetaminophen for adults and 150 mg/kg for children.” In adults, about 125-150 mg/kg is believed to cause liver injury.
FDA Lowers Limit on Tylenol to Reduce Risk of Overdose
In response to the growing incidence of accidental Tylenol overdoses, in 2011 the FDA published a Safety Communication to warn about the danger. They placed a Boxed Warning on the label for Tylenol and reduced the maximum dose to 325-mg of acetaminophen. In July 2011, Johnson & Johnson and McNeill limited the maximum daily recommended dose of Tylenol from 4,000-mg to 3,000-mg in one day.