New research has found that the most commonly taken antidepressant drug does little or nothing to relieve symptoms of depression.

Published in the Lancet Psychiatry journal, the study showed that most people taking sertraline saw little or no improvement in their symptoms during the initial six to twelve weeks.

The University College London research is the largest ever seen in this area, surveying 653 people with depressive symptoms. Split into two groups, one group was given sertraline for twelve weeks whilst the other was given a dummy drug.

The findings showed that depressive symptoms were 5% lower after six weeks in the sertraline group, which meant the drug had “no convincing evidence” of effect.

The 13% reduction among that group after twelve weeks was “weak”, according to researchers.

Research has shown however that sertraline does reduce anxiety, with a 21% reduction after six weeks of taking it. .