Antidepressant medication may reduce empathic responses to the pain of others

A team of scientists in Austria have found evidence that antidepressant medication — rather than depression itself — can lead to reductions in empathy. Their findings appear in the journal Translational Psychiatry.

“Although previous research reported reduced empathy in acute depression, we realized that these previous studies investigated groups of patients who were already undergoing antidepressant treatment,” explained study author Markus Rütgen of the University of Vienna.

“As it has been shown that antidepressants such as serotonergic reuptake inhibitors influence emotional processing, we assumed that the previously reported lowered empathy could be related to the treatment, not to depression itself. Our study design allowed us to clearly disentangle effects of an acute episode of depression and antidepressants on empathy.”

The researchers recruited 29 patients with acute depression, and tested their empathic responses to the pain of others on two occasions.

Before they had received any medication, participants underwent functional magnetic resonance imaging (fMRI) while watching videos of people undergoing painful medical procedures. The empathy tests were repeated after three months of psychopharmacological treatment with antidepressants (mostly selective serotonin reuptake inhibitors). Their empathic responses were compared to a control group of 35 non-depressed participants.

Before treatment, the researchers observed no differences between the depressed participants and the control group. After treatment, however, depressed participants reported their level of empathy to be lower, and brain activation was reduced in areas previously associated with empathy.

In addition, reductions in self-reported empathy were correlated with reductions in depression symptom severity.

“While empathy during an acute episode was found to be on normal levels, antidepressant treatment seemed to downregulate empathic responses to the pain of others,” Rütgen told PsyPost.

“What we found appears to be another side effect of antidepressants that had not been known so far. Knowing about such side effects is important, as it helps people making informed decisions and choose between different treatment options.”

All research includes some limitations, and the current study is no exception.

“As this was the first longitudinal study on the topic, more research is needed to confirm our findings and possibly extend them to other forms of antidepressant treatment. The persistence of the effects could not be tested within the present study. Future studies should also investigate the impact of antidepressants on empathy for positive emotions, which was not tested in our study,” Rütgen said.

The study, “Antidepressant treatment, not depression, leads to reductions in behavioral and neural responses to pain empathy“, was authored by Markus Rütgen, Carolina Pletti, Martin Tik, Christoph Kraus, Daniela Melitta Pfabigan, Ronald Sladky, Manfred Klöbl, Michael Woletz, Thomas Vanicek, Christian Windischberger, Rupert Lanzenberger, and Claus Lamm.