Acetaminophen Reduces Empathy

Merriam-Webster defines empathy as: the feeling that you understand and share another person’s experiences and emotions: the ability to share someone else’s feelings.

Empathy is an important ability to cultivate because it helps promote fulfilling interpersonal relationships. A new study, however, indicates that empathy may be blunted in people who take acetaminophen for pain.

What Is Acetaminophen? 

Acetaminophen bottle with two red tablets and mortar and pestle.

Acetaminophen is the main constituent in the over-the-counter painkiller Tylenol, and it’s also the most commonly taken drug in the United States. According to the Consumer Healthcare Products Association, acetaminophen is an ingredient in more than 600 medications.

Studies indicate that long-term, heavy use of acetaminophen may result in kidney disease and bleeding in the digestive tract, and increased risk of heart attack, stroke and high blood pressure.

Acetaminophen’s Effects on Empathy

Ohio State University researchers conducted two studies that suggest acetaminophen reduces your ability to feel empathy for other people’s physical and emotional pain. These studies confirm prior research that showed that acetaminophen dulls emotions, such as joy.

“These findings suggest other people’s pain doesn’t seem as big of a deal to you when you’ve taken acetaminophen,” said Dominik Mischkowski, co-author of the study and a former Ph.D. student at Ohio State, now at the National Institutes of Health. “Acetaminophen can reduce empathy as well as serve as a painkiller.”

For the first study, researchers divided 80 college students into two groups unbeknownst to them. Forty of the students drank a beverage with 1000 mg of acetaminophen, while the other 40 drank a placebo with no drug. One hour after exposure, all participants read eight short descriptions of people’s physical or mental pain, and then rated what they thought that pain felt like on a scale of 1 to 5, with 1 representing no pain and 5 representing the worst pain imaginable. The students who drank acetaminophen rated the pain less severe across the board.

For the second study, researchers set 114 college students up the same way—half in a control group and half in the experimental acetaminophen group. They exposed the students to unpleasant doses of white noise ranging from 75 to 105 decibels, and then had students rate the unpleasantness level of the noise from 1 to 5, with 5 being the most unpleasant. Students were then asked to rate how unpleasant others would consider the noise, and those who drank the acetaminophen rated the unpleasantness lower for both themselves and others.

“Acetaminophen reduced the pain they felt, but it also reduced their empathy for others who were experiencing the same noise blasts,” Mischkowski explained.

For the second part of that same experiment, participants met three other volunteers and briefly mingled. They were then asked to watch a video game that the students they just met were participating in together (they really weren’t, but the viewers were led to believe they were). One of the participants was deliberately ostracized by the other two when playing. When asked to rate how hurt the left out player felt, students who took acetaminophen rated his/her feelings as less affected than did participants who drank the placebo.

“In this case, the participants had the chance to empathize with the suffering of someone who they thought was going through a socially painful experience,” said Baldwin Way, who is an assistant professor of psychology and member of the Ohio State Wexner Medical Center’s Institute for Behavioral Medicine Research. “Still, those who took acetaminophen showed a reduction in empathy. They weren’t as concerned about the rejected person’s hurt feelings.”

Researchers don’t know how acetaminophen blocks the empathy response, but a 2004 study showed that an analysis of brain scans of people undergoing physical pain while at the same time imagining that same pain being experienced by others showed that the same part of brain for empathy and personal pain were lit up, suggesting that what affects one, can affect the other.