Second-generation antidepressants differ little in their efficacy for treating major depressive disorder, according to a report in the Annals of Internal Medicine.

The results of studies that have compared these drugs suggest “only minimal differences in efficacy, although some of the drugs come with an increased risk of certain side effects,” said Dr. Richard A. Hansen from University of North Carolina at Chapel Hill. “Understanding the likelihood of these side effects and matching this information with patient’s lifestyle and preferences may help improve drug treatment of Depression.”

Hansen and his colleagues reviewed the medical literature in an effort to compare the effectiveness and tolerability of six selective Selective Serotonin Reuptake Inhibitors (SSRI’S) and four other second-generation antidepressants: bupropion (Wellbutrin), duloxetine (Cymbalta), mirtazapine (Remeron), and venlafaxine (Effexor).

None of the SSRIs appeared to differ significantly in effectiveness, speed of patient response, or quality of life outcomes, the authors report. Most trials also showed SSRIs and other second-generation antidepressants to have similar efficacy, speed of response, and resulted in comparable patient quality of life, the report indicates.

Overall, side effects occurred at similar rates among antidepressants, the researchers note, though individual antidepressants emerged as having higher rates of specific side effects (more nausea and vomiting with venlafaxine and fewer sexual side effects for bupropion, for example).

“Additionally, some medications differ in cost and dosing interval,” Hansen said. “Without understanding a patient’s preferences for these aspects of treatment, it’s difficult to make a recommendation.”

“In the absence of patient preferences,” Hansen said, “I would probably start with generic fluoxetine (Prozac), citalopram (Celexa), or Bupropion.”

Future research on drug treatment for patients with major Depression “should include large, high-quality effectiveness trials,” the investigators add. “Choosing the agent that is most appropriate for a given patient is difficult.”

SOURCE: Annals of Internal Medicine, September 20, 2005.