Thursday, April 24, 2014

Acetaminophen Caution and Guidance

We often take Tylenol pills or other acetominophen products (like some night time cold remedies) without thinking of them as drugs with possible harmful side effects.  An article in Medscape by Charles Argoff, entitled "Acetaminophen Caution and Guidance," reminds us to be careful. He says doctors should advise patients to read the labels of the prescription and over-the-counter medications so that they do not take multiple acetaminophen-containing products at the same time. Also, they should advise patients not to drink alcohol while taking acetaminophen-containing products. Excerpts:

Between 1998 and 2003, acetaminophen was the leading cause of acute liver failure in the United States, with 48% of these acetaminophen-related cases of liver failure being associated with accidental overdoses. Summarizing data from 3 different surveillance systems, there were an estimated 56,000 emergency department visits, 26,000 hospitalizations, and 458 deaths related to acetaminophen-associated overdoses per year from 1990 through 1998. A study from 22 medical centers in the United States that was completed in 2003 and was confirmed in a separate study in 2007, demonstrated that a high percentage of instances of liver injury due to acetaminophen were related to unintentional overdoses. In other words, the patient took too much by mistake.

On January 14, 2014, the FDA recommended that healthcare professionals discontinue prescribing and dispensing prescription combination drug products that contain more than 325 mg of acetaminophen per tablet, capsule, or other dosing form. Even before that, in 2011 the FDA had asked manufacturers of prescription combination drug products containing acetaminophen to limit the amount of acetaminophen to no more than 325 mg in each tablet, capsule, or other dosing method by January 14, 2014.

In this particular directive, the FDA noted that severe liver injury with acetaminophen had occurred in patients who took more than the prescribed dose of an acetaminophen-containing product within a 24-hour period, took more than 1 acetaminophen-containing product at the same time, and/or who drank alcohol while taking acetaminophen products. While noting also that acetaminophen is widely used in many over-the-counter products, including over-the-counter cold products, the FDA directive did not provide any regulatory action regarding these particular products. The FDA did advise that many consumers are often unaware that many products contain acetaminophen, and, therefore, consumers could easily take too much by accident. But no actions were taken in regard to over-the-counter products.

1 comment:

Anonymous said...

Paul: interesting points - as an M.D., in the average patient I feel regular 'prescription strength' (up to 4g/day) benefits outweigh the risks of resorting to other analgesics, namely the opiates. With that said, we desperately need a new class of analgesics with both a limited addictive potential as well as low systemic toxicity. Whoever crystallizes that product would certainly retire early!