(AP) -- Johnson & Johnson said Thursday that it's reducing the maximum daily dose of its Extra Strength Tylenol pain reliever to lower risk of accidental overdose from acetaminophen, its active ingredient and the top cause of liver failure.

The company's McNeil Consumer Healthcare Division said the change affects Extra Strength Tylenol sold in the U.S. - one of many products in short supply in stores due to a string of recalls.

Starting sometime this fall, labels on Extra Strength Tylenol packages will now list the maximum daily dose as six pills, or a total of 3,000 milligrams, down from eight pills a day, or 4,000 milligrams. McNeil will also reduce the maximum daily dose for its Regular Strength Tylenol and other adult pain relievers containing acetaminophen, beginning next year.

Besides Tylenol, acetaminophen is the active ingredient in the prescription painkillers Percocet and Vicodin and in some nonprescription pain relievers, including NyQuil and some Sudafed products. People taking multiple medicines at once don't always realize how much acetaminophen they are ingesting.

Two years ago, a panel of advisers to the Food and Drug Administration called for sweeping restrictions to prevent accidental fatal overdoses of acetaminophen, the most widely used pain killer in the country.

"Acetaminophen is safe when used as directed," Dr. Edwin Kuffner, McNeil's head of over-the-counter medical affairs, said in a statement. "McNeil is revising its labels for products containing acetaminophen in an attempt to decrease the likelihood of accidental overdosing."

Kuffner noted many people taking multiple medicines don't realize some of them contain acetaminophen, or don't read or follow the dosing instructions.

McNeil spokeswoman Bonnie Jacobs said other makers of pain relievers are likely to follow suit. She said the change is not related to the series of 25 recalls over the past 23 months of tens of millions of bottles of Tylenol and other nonprescription drugs, several prescription drugs and other products made by Johnson & Johnson.

Excessive use of acetaminophen can cause liver damage and is blamed for about 200 fatal overdoses every year in the U.S. Acetaminophen overdoses send 56,000 people to the emergency room annually.

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