Could Antidepressant Use Among Chronic Pain Sufferers Lead to Personality Changes?

A new report in the Archives of General Psychiatry has found that patients who used an SSRI named paroxetine to treat depression experienced signficantly decreased levels of neuroticism and increased feelings of extraversion as compared to cognitive therapy and placebo groups.

Both neuroticism, marked by negative emotions and emotional instability, and extraversion, characterized by socially outgoing behavior and positive emotions, are depression risk factors that have been linked to serotonin, a neurotransmitter in the brain that affects mood.

Working to keep serotonin in the brain for longer periods of time, paroxetine (e.g. brand names Paxil, Pexeva) and other SSRIs like sertraline (Zoloft), citalopram (Celexa), escitalopram (Lexapro) and fluoxetine (Prozac) are commonly prescribed to treat depression and closely-related disorders like chronic pain.

In the study, 240 adults with major depressive disorder were randomly assigned into different groups, with 120 of the adults taking paroxetine for their depression, 60 undergoing cognitive therapy and the other 60 receiving a placebo during a 12-month time period.

The personalities and depression symptoms of the patients were assessed before, during and after treatment, with all three groups reporting improvements in depression following their respective treatments.

However, patients who took paroxetine experienced significant personality changes in comparison to the placebo group, including as much as 6.8 times a difference in neuroticism and 3.5 times a change in extraversion.

According to the study’s researchers, these findings could challenge the theory that personality changes following antidepressant use are simply the result of alleviating depression symptoms and rather indicate that the biomechanical properties of SSRIs actually produce separate changes in personality.