By now, most Americans have at least heard about the opioid addiction crisis in this country – even those who haven’t been directly impacted by it themselves. The CDC reports that deaths due to overdose of prescription medications such as oxycodone, fentanyl, morphine and other opioid-based narcotics increased 400% between 1999 and 2016.

However, there is another drug that, while not quite as deadly as opioids, has been killing far more people. These are benzodiazepines, more popularly known as “benzos,” which include common prescription drugs such as Valium and Xanax. During that same period, overdose deaths from such medications rose by nearly 700%. According to a report from the National Institute on Drug Abuse, over 30 percent of opioid-related deaths involve having taken some form of benzodiazepine at the same time.

Benzodiazepines are a class of psychoactive medications, or minor tranquilizers, that are used to treat anxiety and sleep disorders as well as convulsions and muscular spasms. The first benzodiazepine medication was discovered by a Polish chemist named Leo Sternbach, who began working for Swiss-based pharmaceutical company Hoffman-LaRoche in 1940.

Fleeing Europe for the U.S. during the Second World War, he was able to secure a position at the company’s plant in Nutley, New Jersey, where he made his discovery in 1955. That medication, chlordiazepoxide, was eventually marketed by LaRoche as Librium starting in 1960. Three years later, an improved version, sold under the brand name Valium, arrived on pharmacy shelves. Eventually, Valium became the most widely-prescribed medication in America, with more than 2.3 billion prescriptions written in 1978 alone.

Abuse of sedatives and tranquilizers has long been an issue in the U.S. According to history professor David Herzberg, an expert on drug policy and prescription drug abuse, the problem has been going on for nearly a century. During the First World War, doctors began switching patients from morphine, opium, and heroin (which were legally sanctioned at the time) to a new class of drugs, known as barbiturates. However, barbiturates were even more addictive than opioids. By the 1940s, the death rate from barbiturates was higher than the current figures associated with opioids.

When they first came on the market, benzodiazepines were considered safer than barbiturates, which is true: a person would have to take 100 times the recommended dosage before risking death (as opposed to barbiturates, which are fatal at 10 times the prescribed dose). Nonetheless, benzodiazepine is still addictive, habit-forming,  and can even worsen the symptoms they are designed to treat – which is why they are controlled substances today.

At this point, it should be noted that N.I.H. research indicates that up to 90 percent of benzodiazepine overdose fatalities also involve the use of opioids. Another study, recently published in the Journal of Clinical Medicine, found that 80 percent of the recreational use of benzodiazepine was done in combination with alcohol – which amplifies the effect.

While people have looked for ways to “get high” throughout history, the problem has intensified in the U.S. over the past three decades. Not coincidentally, that period has also seen growing economic inequality and insecurity due to government policy that favors the wealthy and powerful, designed to disenfranchise and disempower the majority. In the end, drug abuse and addiction is not a problem in and of itself – it is the symptom of a deeper societal disorder.

Until the underlying disease is addressed, the symptoms will continue.