U.S. health regulators are requesting a limit on the amount of acetaminophen in prescription pain medicines in an effort to curb the risk of liver damage.
The move announced on on Thursday aims to limit combination drugs such as the opioids Percocet and Vicodin to 325 milligrams of acetaminophen per pill and calls for them to carry a "black box" warning about potential liver failure.
Some of these medicines now contain as much as 750 milligrams of acetaminophen, a drug also sold over the counter in lower doses as a generic painkiller and Johnson & Johnson's Tylenol.
"This change will provide an increased margin of safety to help prevent liver damage due to acetaminophen overdosing, a serious public health problem," the U.S. Food and Drug Administration wrote in a public notice.
The move affects products made by Johnson & Johnson, Endo Pharmaceuticals Holding Inc, Watson Pharmaceuticals Incorporated and Boehringer Ingelheim's Roxane Laboratories unit, among others.
FDA said it was asking affected companies to comply but stopped short of ordering the actions. Changes would be phased in over three years. Acetaminophen has long been know to cause liver damage if patients overdose or take multiple products that contain the ingredient.