Attention to America’s drug epidemic is usually focused mostly on overdose deaths from opioids, and for good reason. Though heroin and prescription painkillers are a problem, deaths resulting from benzodiazepine overdoses have been increasing.

Benzodiazepines are a class of sedatives that include Valium, Xanax and Klonopin. An estimated 1 in 20 United States adults fills a benzo prescription over the course of a year, a prescription most commonly given to treat anxiety, mood disorders, and insomnia. Researchers at Albert Einstein College of Medicine, Montefiore Health System and the Perelman School of Medicine at The University of Pennsylvania took a look at national trends in benzo prescriptions and fatalities from the drugs, about which little was previously known.

“We found that the death rate from overdoses involving benzodiazepines, also known as ‘benzos,’ has increased more than four-fold since 1996 — a public health problem that has gone under the radar,” said Dr. Marcus Bachhuber, lead author of the study and assistant professor of medicine at Einstein and attending physician, internal medicine, at Montefiore, in a statement. “Overdoses from benzodiazepines have increased at a much faster rate than prescriptions for the drugs, indicating that people have been taking them in a riskier way over time.”

The research team looked to two sources for data on benzo use and fatalities: The Medical Expenditure Panel Survey, which provides a nationally representative sample of healthcare purchases including prescription drugs; and cause-of-death reports from the Centers for Disease Control and Prevention. The analysis revealed that the number of adults purchasing a benzodiazepine prescription increased by 67 percent over an 18-year period between 1996 and 2013. For those with prescriptions, the average quantity filled through the year doubled. Most worryingly, the overdose death rate increased from 0.58 deaths per 100,000 adults in 1996 to 3.14 deaths per 100,000 adults in 2013.

“The greater quantity of benzodiazepines prescribed to patients — more than doubling over the time period — suggests a higher daily dose or more days of treatment, either of which could increase the risk of fatal overdose,” explained Dr. Joanna Starrels, senior author and associate professor of medicine at Einstein and attending physician, internal medicine at Montefiore.

Starrels offered a couple possible explanations for the increase in benzodiazepine deaths.

“People at high risk for fatal overdose may be obtaining diverted benzodiazepines (not from medical providers) and we know that combining benzodiazepines with alcohol or drugs — including opioid painkillers — can lead to fatal overdoses,” she said, also noting that opioid prescribing rose during the study period as well, and that opioids are involved in 75 percent of overdose cases involving benzos.

Researchers suggest emphasizing the danger of overdose when taking benzodiazepines with opioid painkillers or with alcohol, along with suggesting talk therapy as an alternative to benzos for treating anxiety.

Source: Bachhuber M, Starrels J, et al. Increasing benzodiazepine prescription and overdose mortality in the United States, 1996-2013. American Journal of Public Health. 2016.