In the United States, more people are prescribed antidepressants than any other country in the world. Still, the drug’s efficiency and mode of action (MoA) is largely unknown.
So do antidepressants really work? In Germany, the use of antidepressants has risen 46% in just four years. Spain and Portugal saw a rise of 20% in the same period. Iceland was in the lead in overall use with around 1 in 10 individuals taking an antidepressant daily.
Currently, 11% of Americans over the age of 12 are on some form of antidepressant.
With the use of these drugs skyrocketing, does that mean they actually work?
In 2008, researchers put together a meta-analysis of antidepressant trials that had been registered with the Food and Drug Administration as evidence when getting these drugs approved. Pharmaceutical companies had to provide the results of these trials to the F.D.A regardless of their findings.
The researchers included 74 studies in the meta-analysis which totaled more than 12,000 patients, for drugs approved between 1987 and 2004. Around half of these studies contained “positive” results which meant the antidepressant performed better than the placebo. The other half were considered “negative”. Now if you looked at published studies, you’d see a much different picture. Almost all the positive studies are there, and only three of the negative studies appear in the published literature. Many of the studies were not published and 11 were published but changed to appear positive.
Another meta-analysis was done the same year which used the same F.D.A data but asked different questions. The study found the efficiency of antidepressants was minimal for individuals with moderate depression and small for those with major depression.
The take-home message of both of these meta-analysis studies is that the effectiveness of antidepressants had been overstated.
New Antidepressant Data
Recently, the most comprehensive antidepressant study to date was published.
Researchers in this study looked at both published and unpublished double-blind randomized controlled trials beginning in 2016. The studies included looked at both placebo-controlled and head-to-head studies of 21 antidepressants.
The researchers used a “network meta-analysis technique” which allows multiple types of treatments to be compared.
Over 520 trials and 116,000 participants were included in this meta-analysis. 86 of the 522 were unpublished found on trial registries and company websites. The researchers went as far as asking authors for unpublished data that was not included in the studies found. More than half of the authors provided additional data.
The good news is that all of the antidepressants were found to be more effective than the placebos. They drugs varied in terms of efficacy and tolerance.
Additional good news is that the smaller trials did not have substantially different results from the larger trials. There was also little evidence that industry sponsoring trials affected response and dropout rates. BUT the vast majority of trials are funded by the pharmaceutical companies. As a consequence, this meta-analysis might not have had adequate data on non-industry studies to properly assess if a variation exists.
The researchers noticed signs of a “novelty” bias where newly released antidepressants seemed to perform better and lose effectiveness in later years.
The bad news is that despite the fact that there had been statistically significant differences, the effect sizes remained mostly minor. The benefits also applied only to individuals who have been suffering from major depression for a short period of time.
Due to lacking decent data, we do not know for sure how well antidepressants work for those suffering from mild symptoms, specifically if they have been on the meds for months to years. Most people probably fall into that category and are still being prescribed antidepressants for long periods of time. We cannot determine if such use is the placebo effect versus an actual change in brain chemistry.
What Reddit Has to Say
Note: anecdotal data can be a powerful source of information when used properly. This info should be used alongside your own research.
As mentioned, SSRIs and antidepressants do work, but to what degree and length are questionable. User /u/HammerAndFudgsicle from Reddit commented:
Reddit user Noobpsych stated it helped, but it was difficult to stop the drug:
Paxil helped me get out of an awful period of anxiety with panic attacks. It was a bitch and a half to get off of, though.
Others saw negative side effects:
Even with so many antidepressant studies, many questions still go unanswered. Honestly, many of the drug companies may not care to know or be interested in the results of further trials. These drugs are already widely used and no one is requiring more data from them. If a patient wants info, they will need to do the research themselves.