Why antidepressants are not effective

Kathleen Blanchard's picture

Medications used to treat depression may be entirely missing the mark according to results of a new study. According to background information from the research, over half of antidepressants fail to bring relief to depression sufferers. The findings come from the Northwestern University Feinberg School of Medicine, showing that antidepressant medications are not effective because long held notions about what triggers depression are wrong.

According to Eva Redei, a long time depression researchers, neither stress nor do neurotransmitters in the brain trigger symptoms of depression. Antidepressants on the market are designed to increase the uptake of serotonin, or stimulate dopamine and norepinephrine in the brain to treat depression. Redei, using genetically engineered rats says there is no overlap between stress and depression related genes, which is why antidepressants fail. The scientist says antidepressants do not treat the real cause of depression.

Redei and her team used rats genetically engineered to become severely depressed. The group isolated specific genes in the group of rats, and then compared them to four genetically different strains of rats, exposing them to chronic stress for two weeks. Next, Redei studied gene changes that increased or decreased in all four strains in the same brain regions. A comparison was made between rats genetically altered for depression, and genes from the rats exposed to chronic stress that were a completely different strain.

Redei explains, "If the 'stress causes depression theory' was correct, there should have been a significant overlap between these two sets of genes," she said. "There weren't." The findings suggest that stress does not play a role in triggering depression, and that current antidepressants are not treating the cause of depression.


Thirty thousand genes were studied in the area of the brain related to depression - 254 genes related to stress and 1275 genes related to depression. Only five genes overlapped a finding that Redei calls “insignificant”.

Redei says most testing done to develop antidepressants is based on the theory that stress causes depression. "They stress the animals and look at their behavior," she said. "Then they manipulate the animals' behavior with drugs and say, 'OK, these are going to be good anti-depressants.' But they are not treating depression; they are treating stress."

A second part of the study showed that depression begins when neurons in the brain develop, and are related to how those neurons function. Redei says that antidepressant drug developers “have been focusing on the effect, not the cause," she said. "That's why it takes so long for them to work and why they aren't effective for so many people."

Redei says using rats to study depression is applicable to humans because of the “remarkable” similarity in brain structure of human and rodent brains. The new findings suggest that antidepressants are not effective because they are not really treating depression.

Source: Northwestern University