A new study suggests the popular painkiller Tylenol does more than reduce pain — it can actually reduce your ability to imagine other people’s pain. Researchers at Ohio State University conducted three experiments on college students to test whether acetaminophen, the active ingredient in Tylenol and many other prescription and over-the-counter painkillers, affects users’ abilities to empathize with others who are experiencing physical or emotional pain. Their findings were published in the journal Social Cognitive and Affective Neuroscience.
The first experiment called for 80 college students to consume 1,000 mg of acetaminophen and subsequently assess various scenarios of someone experiencing pain. One scenario featured a character receiving a knife wound that reached the bone; another involved a person grieving the loss of his father. The students were asked to rate the pain on a scale of one to five. These ratings were compared to a control group that had consumed a placebo.
The second study exposed 114 college students to short samples of white noise ranging from 75 to 105 decibels. They were asked to rate the unpleasantness of the sound blasts on a scale of one to ten; they were also asked to rate how much displeasure they imagined others might feel from the sounds. These ratings were again compared to a control group that had not consumed acetaminophen.
In both studies, researchers say the college students who had consumed acetaminophen perceived significantly less suffering in others. Dominik Mischkowski, co-author of the study and a former Ph.D. student at Ohio State, believes the findings are important in understanding how popular painkillers reduce feelings of empathy.
“These findings suggest other people’s pain doesn’t seem as big of a deal to you when you’ve taken acetaminophen,” Dominik said in a statement. “Acetaminophen reduced the pain they felt, but it also reduced their empathy for others who were experiencing the same noise blasts.”
A third experiment introduced a social gaming component to the study. The college students watched scenes of three participants meeting and socializing. In the “game,” two of the participants excluded the third. The students were asked to rate the emotional pain of the excluded individual. Again, the group that had consumed acetaminophen rated the pain lower than the control group.
“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, a psychology professor at Ohio State and co-author of the study. “Still, those who took acetaminophen showed a reduction in empathy. They weren’t as concerned about the rejected person’s hurt feelings.”
“When people feel overwhelmed with uncertainty in life or distressed by a lack of purpose, what they’re feeling may actually be painful distress,” said Daniel Randles, who conducted a similar experiment in 2013. “We think that Tylenol is blocking existential unease in the same way it prevents pain, because a similar neurological process is responsible for both types of distress.”
In addition to these psychological effects, Tylenol is considered the most deadly over-the-counter painkiller on the market, believed to cause significant liver toxicity. As many as 78,000 Americans visit emergency rooms each year because of acetaminophen overdose.
The researchers intend to conduct similar research on the effects of ibuprofen, another popular and widely-used over-the-counter pain treatment.