Can Acetaminophen Ease Psychological Pain?

Headaches and heartaches. Broken bones and broken spirits. Hurting
bodies and hurt feelings. We often use the same words to describe
physical and mental pain. Over-the-counter pain relieving drugs have
long been used to alleviate physical pain, while a host of other
medications have been employed in the treatment of depression and
anxiety. But is it possible that a common painkiller could serve double
duty, easing not just the physical pains of sore joints and headaches,
but also the pain of social rejection? A research team led by
psychologist C. Nathan DeWall of the University of Kentucky College of
Arts and Sciences Department of Psychology has uncovered evidence
indicating that acetaminophen (the active ingredient in Tylenol) may
blunt social pain.

“The idea–that a drug designed to alleviate physical pain should reduce
the pain of social rejection–seemed simple and straightforward based on
what we know about neural overlap between social and physical pain
systems. To my surprise, I couldn’t find anyone who had ever tested this
idea,” DeWall said.

According to a study due to be published in the journal Psychological
Science, DeWall and colleagues were correct. Physical and social pain
appear to overlap in the brain, relying on some of the same behavioral
and neural mechanisms.

DeWall and colleagues investigated this connection through two
experiments. In the first experiment, 62 healthy volunteers took 1,000
milligrams daily of either acetaminophen or a placebo. Each evening,
participants reported how much they experienced social pain using a
version of the “Hurt Feelings Scale” – a measurement tool widely
accepted by psychologists as a valid measure of social pain. Hurt
feelings and social pain decreased over time in those taking
acetaminophen, while no change was observed in subjects taking the
placebo. Levels of positive emotions remained stable, with no
significant changes observed in either group. These results indicate
that acetaminophen use may decrease self-reported social pain over time,
by impacting emotions linked to hurt feelings.

“We were very excited about these initial findings,” DeWall said. “The
next step was to identify the neural mechanisms underlying the findings.”

In the second experiment, 25 healthy volunteers took 2,000 milligrams
daily of either acetaminophen or a placebo. After three weeks of taking
the pills, subjects participated in a computer game rigged to create
feelings of social rejection. Functional magnetic resonance imaging
(fMRI) employed during the game revealed that acetaminophen reduced
neural responses to social rejection in brain regions associated with
the distress of social pain and the affective component of physical pain
(the dorsal anterior cingulate cortex and anterior insula). In other
words, the parts of the brain associated with physical lit up in the
placebo subjects when they were rejected, while the acetaminophen group
displayed significantly less activity in these brain areas in response
to rejection.

According to the academic paper detailing the experiments: “…findings
suggest that at least temporary mitigation of social pain-related
distress may be achieved by means of an over-the-counter painkiller that
is normally used for physical aches and pains…. Furthermore, many
studies have shown that being rejected can trigger aggressive and
antisocial behavior, which could lead to further complications in social
life…. If acetaminophen reduces the distress of rejection, the
antisocial behavioral consequences of rejection may be reduced as well.”

Researchers caution that readers should not immediately stock up on
acetaminophen to ease social pain and anxiety, noting “[t]o be sure, our
findings do not constitute a call for widespread use of acetaminophen to
cope with all types of personal problems. Future research is needed to
verify the potential benefits of acetaminophen on reducing emotional and
antisocial responses to social rejection.” Long-term use of
acetaminophen has also been linked to serious liver damage, so it is
important for patients to follow all package directions and consult
their physicians if they are contemplating taking any medication for an
off-label use.

“This research has the potential to change how scientists and laypersons
understand physical and social pain. Social pain, such as chronic
loneliness, damages health as much as smoking and obesity. We hope our
findings can pave the way for interventions designed to reduce the pain
of social rejection,” DeWall said.