How the Brain Responds to Drugs for Anxiety and Depression

Kathleen Blanchard's picture

Researchers, when studying the effects of medication use placebos, to test how well a drug really works. They provide real medication to some study participants, and placebos to others. Placebos are drugs that have no medication in them. According to a new study, our genes play a role in how the brain responds to drugs given for anxiety and depression.

Researchers at the Universities of Uppsala and Gothenburg found that forty percent of patients enrolled in a study obtained anxiety relief when given a placebo. The study, published in the Journal of Neuroscience looked at the brains of 108 people with personal with social phobia; using brain camera (PET, positron) to find out that genetic predisposition may be the most important factor when determining medications that work best for treating anxiety, depression and social phobias.


Popular drugs used for anxiety treatment include selective serotonin reuptake inhibitors, (SSRI's). Serotonin is an important brain chemical responsible for emotions. Antidepressants that target serotonin block the brain's ability to prevent serotonin from freely circulating the body. Researchers believe that is how the drugs make us calmer and less depressed. The current research may explain why drug treatment for anxiety and depression is not always successful.

Thomas Furmark, from the University's Department of Psychology led the study. Dr. Furmark says, "It is also possible that genes may explain why some people respond well or poorly on anxiety depressant drugs and psychotherapy". The researchers found that only study participants who possessed the serotonin transporter gene and tryptofanhydroxylas-2 gene experienced decreased serotonin uptake in the brain in response to stress, predicting how well the individual responded to anxiety and stress reduction. The findings show that we process and respond to stress uniquely, depending on our gene. Medications for anxiety and depression may not work in everyone because the gene is missing that suppresses those emotions in the brain.

The study may have important implications regarding how patients with anxiety and depression should be treated. For many, medication may show no benefit. The current research might provide an answer to why some people respond well to placebo medication and why others get no relief from drugs used to treat anxiety and depression.

Source: Uppsala University