This Popular Painkiller is Proven to Dull Human Empathy and Joy

by Anna Hunt

One of the most common over-the-counter drugs used to reduce pain may also be decreasing your ability to be empathetic. Moreover, it may also stifle the magnitude of positive emotions such as joy.

A study out of Ohio State University has found that participants who took acetaminophen were less empathetic when they learned about the misfortunes of others. Acetaminophen is the common ingredient in Tylenol and is also present in hundreds of other medicines, both over-the-counter and prescription, according to the Consumer Healthcare Products Association (CHPA).

A substantial body of functional magnetic resonance imaging (fMRI) research suggests that observing others experiencing pain, activates brain regions that are also activated during one’s own experience of pain. Therefore, the study’s researchers, Dominik Mischkowski, Baldwin Way and Jennifer Crocker, wanted to understand if something that reduced one’s pain also affects how one perceives others who are experiencing pain.

Emotional Side-effects of Acetaminophen

The study compared participants who took a liquid drink with acetaminophen to participants who took a placebo. Three experiments were conducted, all showing the participants who took the painkiller were less empathetic.

In one experiment, participants read short scenarios in which a person was in physical or emotional pain. The study subjects who had taken acetaminophen thought the people in the scenarios experienced less pain and suffering when compared to subjects who did not take the painkiller.

“These findings suggest other people’s pain doesn’t seem as big of a deal to you when you’ve taken acetaminophen.” ~ Dominik Mischkowski, co-author of the study, National Institutes of Health (source)

In another experiment, a different group of participants experienced a number of white noise blasts. They were asked to rate how unpleasant the blasts were to them on a scale of 1 to 10. Then, they were asked to rate how unpleasant they think the noises would be to others.

Similar to the first experiment, the subjects who took acetaminophen rated the noises less unpleasant for themselves and others, when compared to placebo subjects.

“We don’t know why acetaminophen is having these effects, but it is concerning.” ~ Baldwin Way, senior author of the study, Ohio State Wexner Medical Center’s Institute for Behavioral Medicine Research (source)

Finally, in a third experiment, the participants observed an online game between people who they already met. One actor was purposefully excluded out of the game by others. The participants who took acetaminophen rated the feelings of the excluded person as less severe, when compared to the ratings given by the participants who took the placebo.

The study authors conclude:

Because empathy regulates prosocial and antisocial behavior, these drug-induced reductions in empathy raise concerns about the broader social side effects of acetaminophen, which is taken by almost a quarter of adults in the United States each week. (source)

Study co-author Baldwin Way had conducted other research on the psychological impact of acetaminophen. In collaboration with Geoffrey Dursoat of Ohio State University, he studied subjects who viewed 40 photographs from the International Affective Picture System database. The photos ranged from extremely unpleasant to very pleasant. Study participants who took acetaminophen rated positive photos as less positive and negative photos as less negative when compared to the ratings of those who took the placebo.

The study showed that acetaminophen can impact how sensitive we are to both bad as well as good things.

“This means that using Tylenol or similar products might have broader consequences than previously thought. Rather than just being a pain reliever, acetaminophen can be seen as an all-purpose emotion reliever.” ~ Geoffrey Dursoat of Ohio State University (source)

According to the FDA, acetaminophen is safe and effective when used according to label instructions. It has become so popular that in a typical week about 23 percent of American adults use medicine that contains acetaminophen. That’s about 52 million people.

Yet, according to the National Institutes of Health (NIH), taking too much can damage your liver. Furthermore, acetaminophen overdose sends as many as 78,000 Americans to the emergency room annually, killing 1,500. Some studies have found that “taking twice or sometimes even just a little bit more than the daily recommended dose of 4 grams of Tylenol over the course of a few days can result in severe illness and even death.” (source)

Now, considering this new research, should the public be made aware of the drugs potential psychological side effects, regardless of how subtle they may be?