FDA Limits Acetaminophen Dosage in Prescription Meds

Patient Expert

Yesterday the U.S. Food and Drug Administration announced that it is asking manufacturers of prescription combination products that contain acetaminophen to limit the amount of acetaminophen to no more than 325 mg (milligrams) in each tablet or capsule.

Acetaminophen is probably best known by the brand name Tylenol.   Outside the U.S., it is often called paracetamol and on prescriptions it may be labeled as APAP (For example, hydrocodone APAP).   The drugs most affected by this action are opioid pain relievers that are combined with acetaminophen like codeine (Tylenol #3), hydrocodone (Vicodin, Lortab) and oxycodone (Percocet).

"FDA is taking this action to make prescription combination pain medications containing acetaminophen safer for patients to use," said Sandra Kweder, M.D., deputy director of the Office of New Drugs in FDA's Center for Drug Evaluation and Research (CDER). "Overdose from prescription combination products containing acetaminophen account for nearly half of all cases of acetaminophen-related liver failure in the United States; many of which result in liver transplant or death."

Drug manufacturers are being given three years to phase in this change so it is not expected to create a shortage of pain medication.

"There is no immediate danger to patients who take these combination pain medications and they should continue to take them as directed by their health care provider," said Kweder. "The risk of liver injury primarily occurs when patients take multiple products containing acetaminophen at one time and exceed the current maximum dose of 4,000 milligrams within a 24-hour period."

The FDA is also requiring manufacturers to update labels of all prescriptions containing acetaminophen combined with another drug to warn of the potential risk for severe liver injury.

Acetaminophen is also widely used as an over-the-counter pain and fever medication, and is combined with other OTC ingredients, such as cough and cold ingredients. The actions the FDA is taking for prescription acetaminophen products do not affect OTC acetaminophen products at this time.   It's possible they may consider limiting acetaminophen dosage in OTC products later.

My Thoughts...

Although I've been unhappy with other FDA decisions lately, I don't really have a problem with this one.   In 2009, an FDA advisory panel recommended banning prescription medications containing acetaminophen (like Vicodin and Percocet).   Thankfully, the FDA did not go to that extreme.

The main purpose of adding acetaminophen to an opioid is to boost the effectiveness of the opioid.   It is my understanding that just reducing the amount of acetaminophen should not have much, if any, effect on the pain-relieving ability of the medication.

I'm especially pleased that the FDA is giving drug manufacturers three years in which to make the change.   This should enable them to phase in the new dosages without creating any shortages for patients.

For more information on this new ruling, see:   Questions and Answers about Prescription Acetaminophen Products to be Limited to 325 mg Per Dosage Unit
What do you think about this change?   Click on "Comments" below to share your thoughts.

FDA limits acetaminophen in prescription combination products; requires liver toxicity warnings.   FDA News Release. January 13, 2011.

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