Is acetaminophen a carcinogen?

State of California considers declaring acetaminophen a carcinogen. Will that mean Tynelo Cause cancer? Some studies show the painkiller’s association with cancer is unclear. The evidence isn’t totally clear.

California regulators are considering labeling acetaminophen – the drug found in Tylenol and other common pain relievers – as a carcinogen.

Acetaminophen, known outside of the U.S. as paracetamol and used to treat pain and fevers. It is the basis for more than 600 prescription and over-the-counter medications for adults and children, found in well-known brands like Tylenol, Calpol, Excedrin, Panadol, Sudafed, Robitussin and Theraflu.

The state’s Proposition 65 law requires California to warn consumers of any chemicals known to cause cancer or reproductive toxicity. More than 900 chemicals have been added to the state’s list – the largest in the United States – since the law passed in 1986.

California’s Carcinogen Identification Committee, a group of scientists, will determine whether the state deems acetaminophen a carcinogen after public comments close on Jan. 27. If added to the list, regulators could require products containing acetaminophen to carry warning labels.

Evidence for acetaminophen’s link to cancer has been weak enough that the International Agency for Research on Cancer declined to list it as a possible carcinogen following reviews in 1990 and 1999. The U.S. Food and Drug Administration has warned state officials that labeling acetaminophen as cancer-causing would be “false and misleading” and also illegal under federal law.

Johnson & Johnson, Tylenol’s manufacturer, has has not responded to a request for comment.

While the jury is still out on whether or not Tylenol can cause cancer, manufacturer Johnson & Johnson has found itself in hot water in the past for misleading customers about its ingredients. 

The company has agreed to pay $6.3 million to families who bought Infants’ Tylenol between October 2014 and January 2020.

Families filed a class-action suit against the firm for suggesting that Infants’ Tylenol contained a reduced amount of acetaminophen, specially designed for infants. But Children’s Tylenol, a cheaper product, was found to contain the same amount of acetaminophen as Infants’ Tylenol.