The latest generation of antidepressants are no better at helping people than a placebo, new research claims.
Experts from the Department of Psychology at the University of Hull analysed 47 clinical trials using figures released under Freedom of Information rules by the US Food and Drug Administration (FDA).
The researchers, led by Professor Irving Kirsch, examined four common antidepressants and the clinical trials that were submitted to gain licensing approval.
The Selective Serotonin Reuptake Inhibitors (SSRIs) they assessed included Prozac (fluoxetine), Efexor (venlafaxine) and Seroxat (paroxetine).
They found the drugs offered little clinical benefit when both unpublished and published data from the drug companies was analysed.
The scientists wrote: “Drug-placebo differences in antidepressant efficacy increase as a function of baseline severity, but are relatively small even for severely depressed patients.
“The relationship between initial severity and antidepressant efficacy is attributable to decreased responsiveness to placebo among very severely depressed patients, rather than to increased responsiveness to medication.”
The paper in the journal PLoS (Public Library of Science) Medicine concludes: “Using complete datasets (including unpublished data) and a substantially larger dataset of this type than has been previously reported, we find that the overall effect of new generation antidepressant medications is below recommended criteria for clinical significance.”
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