Otsubo T, et al. - The effectiveness and safety of switching the antidepressant formulation from immediate-release (IR) to controlled-release (CR) paroxetine was comprehensively examined by researchers among subjects with major depressive disorder (MDD), who were diagnosed according to the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision, and treated with a stable dose of IR paroxetine for at least 6 months. The switch in the treatment from IR to CR paroxetine possibly led to an improvement in the depressive symptoms and decreased adverse drug reactions (ADRs). Nonetheless, these could be due to the psychological effect of drug switching.