Within the fourteen years, since Prozac, Paxil, and the other SSRIs hit the market, they have considerably changed the ways of treating depression. Currently, nearly seven million American citizens take the antidepressant medications for everything from generalized nervousness to PMS, however there is increasing evidence that their effectiveness may be more marketing hype than miracle cure.
The recent scientific research to weigh in on the subject discovered that the antidepressant medications acted only slightly better than placebos in a group of studies presented to the FDA. The participants of the studies who were taking the dummy pills had approximately 80 per cent of the response visible in patients taking one of the six most widely prescribed antidepressant drugs.
Chief scientist, Irving Kirsch, PhD, tells WebMD that in many of these studies, whilst the difference between medication and placebo was considerable from a statistical standpoint, it did not represent an important difference for patients. His research will appear on July 15 in the American Psychological Association’s electronic publication, Prevention and Treatment.
"We are not claiming that patients do not respond to these medicines," explains Kirsch, who is a psychology professor at the University of Connecticut. "On the contrary, the response is very significant, and that is why there has been this so-called revolution in the treatment of depression. The catch is that the response to placebo is almost as significant."
Selective serotonin reuptake inhibitors (SSRIs) are thought to alleviate depression by increasing the effectiveness of the neurotransmitter serotonin in the brain. In a review published four years ago, Kirsch first indicated that the antidepressant medications are just a little more effective than a placebo. The results of the study were widely criticized by mental health professionals at the time, and Kirsch claims the latest review attempts to address the criticisms.
Kirsh and his team pooled data from roughly forty different studies of six SSRIs that gained FDA approval between 1987 and 1999. The medications included Prozac, Paxil, Zoloft, Celexa, Effexor, and Serzone. All of the studies were conducted in order to compare depression relief among patients treated with the SSRIs with those who were receiving placebos. The patients were not informed which treatment they were receiving, and both groups got better. Using a standardized 50-point depression scale, the pooled results demonstrated that patients treated with antidepressant drugs had a 10-point improvement, while those given placebos got better by 8 points.
Kirsch admits that the design of the placebo-controlled research may hide the true effectiveness of the antidepressant drugs and exaggerate the effectiveness of the placebos. But he also says that the results also undoubtedly indicate that too many people are relying on unproven medications to treat the symptoms of depression.
"People may be better off exploring other options of treatment, for example psychotherapy or physical activity, which has proven to decrease depression. And the side effect of physical exercise is better health. That is much better than the loss of sexual desire and function, tremors, agitation, diarrhea, and nausea that are side effects of SSRIs."
Psychologist Roger P. Greenberg, PhD, claims that it is understandable that the SSRIs have become very popular in such a short time, in spite of the lack of data proving them to be successful. Both patients and their healthcare providers, he adds, have adopted a "fast-mood mentality," where the quick fix is expected for the treatment of depression. Greenberg heads the psychology division at SUNY Upstate Medical University and has already written two books on the limits of treating depression with medications.
"The idea that depression results from a biochemical imbalance that is easily treated with medications has taken hold over the past few years due to the fact that it provides this easy solution," he explains WebMD. "Biochemical imbalance is a handy catch phrase, but there is not a lot of evidence that such a thing really exists."
However, the psychiatrist Michael Thase, MD, defends the role of SSRIs in the treatment of depression, and claims that the recent research offers several new insights. The results, he adds, are less of an indictment of antidepressant medications than a commentary on the human aspect of depression treatment. Cutting a long story short, the research demonstrates the power of belief in a clinician or a treatment.
Thase emphasizes that the placebo effect is not as strong among patients with more severe forms of depression, particularly those with psychotic features like schizophrenia. And he observes that research evaluating the usefulness of nonpharmacological treatments like psychotherapy has similar limitations to medicines research. Thase is a professor of psychiatry at the University of Pittsburgh Medical Center.
"The placebo effect is nothing new," he states. "It doesn’t mean that a medication doesn’t work."
