High anxiety?

U-M researchers look at cannabinoids, genes, medicines and brain scans to find better anxiety treatments

These brain scans and graph show that response to a threat was greatly reduced when study volunteers received THC, compared with placebo. This indicates that the brain's cannabinoid system may... Click here for more information.

ANN ARBOR, Mich. — Right now, about half of all people who take medicine for an anxiety disorder don’t get much help from it. And doctors have no definitive way to predict who will, and who won’t, benefit from each anti-anxiety prescription they write.

But a University of Michigan Medical School researcher and his team are working to bring more certainty to how doctors and patients choose anxiety treatments, by probing the connection between brain activity, genetics and medication.

In a paper last month in the Journal of Neuroscience, K. Luan Phan, M.D., and his former University of Chicago colleagues reported intriguing findings from a brain imaging study in occasional, non-dependent, marijuana users.

In a placebo-controlled design, they made the findings after giving the volunteers delta-9-tetrahydrocannabinol (THC), the active ingredient in marijuana, and exposing them to photographs of emotional faces, which served as signals of social communication. The study results, which showed that THC reduces the response to threat in a brain region called the amygdala, allowed the researchers to zero in on an area of the brain that might serve as a good target for new anti-anxiety drugs.

Now, with a new clinical trial that is currently seeking participants, Phan is searching for more clues as to how anxiety treatment could be tailored to the individual patient, to give the best chance that a treatment will work for him or her.

The new study will test a generic form of the drug Zoloft (sertraline), a selective serotonin reuptake inhibitor (SSRI) approved by the U.S. Food and Drug Administration for social anxiety disorder and other anxiety disorders. Both people with social anxiety disorder and a comparison group of people without anxiety are needed for brain scanning and genetic testing.