A most widely-used Painkiller - acetaminophen - when taken in combination with large amounts of caffeine may potentially cause liver damage.

The toxic interaction could occur not only from drinking caffeinated beverages while taking the painkiller but also from using large amounts of medications that intentionally combine caffeine and acetaminophen for the treatment of migraine headaches, menstrual discomfort and other conditions, the researchers say.

This is the first time that experts warn about the harmful interaction between the combination of painkillers and caffeine.

Such were the findings of a preliminary laboratory study reported in the Oct. 15 print issue of American Chemical Society (ACS)'s Chemical Research in Toxicology.




According to Chemist Sid Nelson, Ph.D., and colleagues, of the University of Washington in Seattle:

"People should be informed about this potentially harmful interaction. The bottom line is that you don't have to stop taking acetaminophen or stop taking caffeine products, but you do need to monitor your intake more carefully when taking them together, especially if you drink alcohol.

The bacteria used in the study were exposed to 'megadoses' of both acetaminophen and caffeine, much higher than most individuals would normally consume on a daily basis. Most people would similarly need to consume unusually high levels of these compounds together to have a dangerous effect, but the toxic threshold has not yet been determined."

Find more details from University of Washington.

A popular brand of acetaminophen is Tylenol.

[Tylenol Acetaminophen Extra Strength, 500 mg, Rapid Release Gels 225 gelcaps available via Amazon]