Should Effexor Be Given with Another Antidepressant?

Dallas, TXAmid reports of Effexor side effects, such as reported Effexor birth defects and concerns about the usefulness of antidepressants, comes a study that suggests taking two antidepressants is no better than taking one. The study, which included an examination of Effexor venlafaxine, found that the additional antidepressant might not be worth the cost.

According to PsychCentral (03/03/11), researchers used data from 665 patients who were diagnosed with major depressive disorder. Those patients were then put into one of three groups: the first group took escitalopram (Lexapro) with a placebo, the second took escitalopram (Lexapro) with buproprion (Wellbutrin), and the third took extended-release venlafaxine (the generic version of Effexor) and mirtazapine (Remeron, a tetracyclic antidepressant).

Researchers found that all three groups had similar outcomes. Patients had remission rates of between 38 and 39 percent in each of the groups, while response rates were approximately 52 percent. Although the remission and response rates were similar, however, the group that was given venlafaxine and mirtazapine was found to have suffered more side effects than the other two groups.

The study, called Combining Medication to Enhance Depression Outcomes (CO-MED), is included in the American Journal of Psychiatry (published online 05/02/11). Researchers concluded, "The combination of extended-release venlafaxine plus mirtazapine may have a greater risk of adverse events [than a single antidepressant or than the other combination of antidepressants]."

Dr. Madhukar Trivedi, a researcher involved in the CO-MED study, was also involved in the STAR*D (Sequenced Treatment Alternatives to Relieve Depression) trial, which found that only approximately 30 percent of patients who take an SSRI (selective serotonin reuptake inhibitor) go into remission in the first 12 weeks of their treatment.

Meanwhile, even patients who appear to have been successfully treated by antidepressants still experience some symptoms of depression, according to research cited by MSNBC (04/27/11). That research involved an analysis of participants in the STAR*D trial, and found that persisting symptoms experienced by patients included sadness, insomnia and difficulty with concentration. The analysis found that up to 75 percent of study respondents reported five or more symptoms of depression, even after receiving treatment in the form of an SSRI.

Because Effexor is not an SSRI, it is not known if the results of that study are extended to the antidepressant. Effexor is in a class of drugs known as SNRIs, serotonin-norepinephrine reuptake inhibitors, a class that is similar to SSRIs but not identical.