Antidepressants Change Personality

A new study by the National Institute of Mental Health (NIMH) suggests that antidepressants such as Prozac and Paxil alter two key personality traits linked to depression – neuroticism and extraversion. "Medication can definitely change people's personalities, and change them quite substantially," says the lead author of the study, Tony Z. Tang, Ph.D., a professor of psychology at Northwestern University in Evanston, Illinois.

In the study, users of Paxil had a lower rate of neuroticism which lead to emotional instability and negative emotions. Users also reported higher amounts of extraversion which increases outgoingness, compared to the placebo group. The more drastic the personality shift, the less likely patients relapsed into depression. Overall, patients became more socially at ease and less sensitive to rejection.

"The theory of how these medications work is actually still a mystery," says Tang, leaving many unanswered questions about these drugs. Patients taking Paxil for eight weeks reported a reduction in neuroticism 7 times greater than the placebo group. Extraversion increased 3.5 times greater than the placebo.