Is Effexor As Effective As Studies Say?

Boston, MAWhen it comes to using Effexor, patients often consider whether or not they will be subject to Effexor side effects, which reportedly include a risk of Effexor birth defects. They probably do not wonder whether Effexor venlafaxine actually works, because the belief is that a drug would not be prescribed unless it did work.

Except that may not be true, some studies suggest, meaning that women and their unborn babies could reportedly be exposing themselves to side effects from a medication that reportedly only works marginally better than a placebo. According to a study published in the New England Journal of Medicine (2008; 358), the effectiveness of antidepressants, including selective serotonin reuptake inhibitors (SSRIs) and serotonin norepinephrine reuptake inhibitors (SNRIs), has been exaggerated. That exaggeration has occurred in the form of studies showing favorable results through the use of antidepressants being published. Meanwhile, doctors are not made aware of studies that find antidepressants are not effective or are only barely effective.

According to the analysis, 74 studies involving 12 antidepressants were sent to the US Food and Drug Administration (FDA) from 1987 through 2004. Of those, 38 studies were considered to show antidepressants in a positive light. Only one of those positive studies went unpublished. By contrast, 36 were considered to have negative or questionable result concerning antidepressants. Twenty-two of those studies went unpublished. Furthermore, researchers said, of the 14 that were published, 11 were published in such a way as to present the negative findings in a positive light.

In other words, even studies that were negative about antidepressants were published to highlight the positives of the drugs.

"According to the published literature, the results of nearly all of the trials of antidepressants were positive," researchers wrote. "In contrast, FDA analysis of the trial data showed that roughly half of the trials had positive results."

Current research involving SSRIs and birth defects suggests a link between the two, but there have been conflicting findings. SSRIs and SNRIs have been linked to an increased risk of persistent pulmonary hypertension of the newborn (PPHN) and other congenital heart defects.

But this study about selective publication of antidepressant effectiveness could have implications for pregnant women who have depression. The first implication being whether the risk of side effects is worth the benefits when there is some question over how beneficial the antidepressants are. The second implication—or at least a question that ought to be raised—being whether or not there are more studies out there that suggest a link between antidepressants and birth defects that have not been published because of their negative findings. It is a lot for a pregnant woman to think about when she is trying to determine how to deal with depression.