ANN ARBOR—Misusing sedatives or tranquilizers signals a credible risk for the abuse of more addictive substances in the near future, according to new research from the University of Michigan School of Nursing's Center for the Study of Drugs, Alcohol, Smoking and Health.
"Once you start using a potentially addictive medicine illegally, you're at a substantially higher risk of using other substances, and this raises the risk of addiction," said lead author Carol Boyd, professor of nursing and women's studies.
"We have seen this phenomenon with the opioid analgesic epidemic, and now we see similar risks with prescribed sedatives and tranquilizers. Tranquilizer and sedative prescriptions have increased in the U.S. and this study shows some of the consequences."
Boyd and her U-M colleagues, Sean Esteban McCabe and Brady West, examined national data from nearly 35,000 American adults, first during a one-year period referred to as Wave One.
They began by looking at how many people were misusing sedatives, such as sleeping pills, or tranquilizers such as Valium, Xanax and muscle relaxers. Misuse includes taking too much of the medication, taking it longer than prescribed, for reasons other than intended such as to get high, or taking someone else's prescription. The same people were re-interviewed three years later in Wave Two.
The researchers found that 76 percent of the people who were misusing sedatives and tranquilizers during Wave One had stopped misusing those drugs three years later in Wave Two.
While this may seem like a positive indication, Boyd and colleagues discovered that 45 percent of the people who had misused the sedatives and tranquilizers during Wave One had a substance use disorder at Wave Two involving other substances—primarily alcohol, marijuana and opioids.
"Tranquilizers and sedatives are Schedule IV medications, which mean they are not believed to be as addictive as other drugs such as many opioids," Boyd said. "For this reason, we should not be surprised that most misusers did not develop an ongoing tranquilizer or sedative addiction.
"However, the worry should be this: sedative and tranquilizer misuse signals an increasing likelihood of developing an addiction to another drug."
The researchers found that young adults, ages 18-25, were most at risk of developing a later alcohol or drug use disorder. Of the people in that age group who misused sedatives or tranquilizers at Wave One, 60 percent of women and 67 percent of men, had a substance use disorder involving other substances three years later. In all age groups, men were more likely to develop additional substance use disorders.
Boyd says it's very rare to find drug misusers, including sedative and tranquilizer misusers, who only partake in one substance. She believes recognizing poly-substance use is a critical piece in preventing and treating substance misuse and addiction.
"We have to retrain clinicians to think differently," she said. "Most drug users are not single drug users. They misuse several substances and often co-ingest them. This puts misusers at risk for overdose, and even death. We must remember that sedatives and tranquilizers contribute to overdose, especially when mixed with alcohol and opioids."
Boyd encourages clinicians to increase patient education about the risks of misuse, as well as how to store and dispose of medications.
Funding for this study was provided by the National Institute on Drug Abuse.