Each year, 14,000 Americans die due to an overdose of opioids such as OxyContin, Percocet, Vicodin or other prescription painkillers, according to the Centers for Disease Control and Prevention (CDC).

But behind that staggering death toll is a hidden risk: Up to one-third of the people who died from opioid overdoses were also taking benzodiazepines, a class of drugs that includes anti-anxiety medications such as Valium and Xanax as well as sleep drugs such as Restoril and Halcion.

Commonly referred to as "benzos," medications from the large category of drugs are also used as muscle relaxants and to prevent seizures.

What’s dangerous about taking an opioid for pain along with, say, a sedative such as Valium is that both drugs affect similar neural pathways in the central nervous system. So combining them compounds the risk of dangerous side effects—extreme drowsiness and very slow, or even stopped, breathing.  

“We’re seeing these tragedies every day in our communities,” says Baltimore Health Commissioner Leana Wen, M.D., “And people who misuse drugs or take illicit substances are not the only ones affected. There are many cases where people were taking these medications together as prescribed by their doctors without realizing the possible harms.”

Alarmingly high numbers of deaths due to opioid overdoses prompted Wen and other health officials and researchers from across the country to file a citizen’s petition with the Food and Drug Administration (FDA) earlier this year, asking for stronger warnings about the risks of opioids and benzodiazepines.

The agency responded in about six months—record time, in FDA terms—and recently issued a ruling requiring black box warnings (the strongest type) for both types of medications—about 400 prescription products in total.

Doctors Aren't Always Aware of the Risk

Despite the growing recognition that it’s dangerous to combine these drugs, research shows that doctors commonly prescribe benzodiazepines for people who take opioids—and vice versa. A recent study based on data from the Rhode Island State Department of Health, for example, found that nearly 60 percent of people who filled a prescription for a benzodiazepine also filled an opioid prescription within 30 days.

“I can tell you from my own experience as an emergency physician that for a long time it was considered standard treatment to prescribe someone with a back injury Percocet for pain and Valium for muscle spasms,” says Wen. Another common scenario is for doctors to prescribe opioids for chronic pain along with a benzodiazepine for associated symptoms such as anxiety, muscle spasms, or sleeplessness.

There’s not good evidence in either scenario that adding the benzodiazepine drug helps people live better, with less pain, or recover faster. “So much of what we do in medicine is based on years of clinical practice rather than scientific evidence,” says Wen. “These new black box warnings are a tool to help educate healthcare providers to update their practice.”

Don't Stop Cold Turkey

Benzodiazepines form a large group of medications that includes anti-anxiety drugs such as alprazolam (Xanax), clonazepam (Klonopin), diazepam (Valium), and lorazepam (Ativan). They also include sleep drugs such as temazepam (Restoril) and triazolam (Halcion). (Those medications are also available as generics.) 

If you aren’t sure if a medication you are taking falls into that category, or whether it's OK to take with an opioid, call your doctor or pharmacist to ask.

If it turns out that you are taking both an opioid and a benzodiazepine, Wen does not advise that you stop either medication abruptly. That could lead to serious side effects such as seizures or severe withdrawal symptoms.

Instead, she advises having a thorough discussion with your doctor about the risks and benefits of each medication as well as the alternatives. For example, research shows that modifying sleep habits works well to combat insomnia, without any of the risks of sleep drugs.

And nondrug approaches such as exercise and physical therapy have been shown to reduce pain and improve function just as well—or better—than opioids for many people coping with chronic pain.

If you and your doctor decide that the combination of medications makes sense for you, discuss ways to minimize your risk. That includes, for example, not exceeding recommended doses of either drug and not drinking alcohol, which is also sedating and increases the risk of potentially deadly side effects.

Finally, anyone who takes an opioid pain drug should talk to his or her doctor about getting a prescription for naloxone, an opioid antidote that can reverse a possible overdose in minutes.

The CDC recommends naloxone for people who take opioids and benzodiazepines together or have other risk factors for opioid overdose, including taking higher doses of opioids (50 mg or more of hydrocodone or 33 mg of OxyContin daily) or having a history of substance abuse or overdose. Read more about how to get naloxone for free or at a low cost.

Editor's Note: This article and related materials are made possible by a grant from the state Attorney General Consumer and Prescriber Education Grant Program, which is funded by the multistate settlement of consumer-fraud claims regarding the marketing of the prescription drug Neurontin (gabapentin).