Benzos like Xanax may shrink the brain in the long term, study hints

Long-term use of benzodiazepines may shrink certain parts of the brain, new research suggests. 

The findings support current guidelines on the use of this class of drugs, which caution against using benzodiazepines for extended periods of time. 

Benzodiazepines, also known as "benzos," are sedative drugs commonly prescribed to treat numerous conditions, including insomnia, anxiety and seizure disorders. They work by slowing down the activity of the central nervous system, meaning the brain and spinal cord. This can relax a person's mood, relieve muscle spasms and also cause people to feel sleepy. 

These drugs, which include Xanax, are highly addictive and previous research has shown that long-term use comes with a risk of memory and movement issues. As such, the U.S. Food and Drug Administration (FDA) recommends that benzodiazepines are prescribed at the lowest dose possible and for the minimum time required to achieve the desired clinical effects — usually around two to four weeks. 

Despite these concerns, evidence suggests that between 6% and 15% of patients prescribed benzodiazepines use the drugs for more than six months.

In the new study, published Monday (July 1) in the journal BMC Medicine, researchers have revealed another reason to be cautious about prolonged benzo use: it use may speed up the natural age-related dwindling of two regions of the brain involved in memory and mood regulation, called the hippocampus and the amygdala. 

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