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Dangerous Drug Combinations That Can Cause Overdose

Most Dangerous Drug Combinations

According to the Centers for Disease Control and Prevention (CDC), combining drugs together is never considered safe, as doing so can result in more intense, unpredictable, and possibly fatal effects. In fact, the CDC reports that approximately 70% of all drug overdoses in 2022 were opioid-involved, meaning that opioids were not the sole drug to cause these overdoses, but instead a contributing one – inferring that other substances were also being used alongside opioids at the time of these overdoses.

Being aware of the several life-changing and potentially fatal outcomes of combining drugs is absolutely imperative in order to prevent an outcome that cannot be reversed. With that in mind, we’ve listed a few lethal drug combinations that are both highly dangerous and deadly.

Gray Death: Dangers of Combining Opioids

This is a fairly new combo making national headlines. The deadly mixture is made of a variety of opioids, including heroin, fentanyl, carfentanil, and a lesser-known synthetic opiate known as U-47700. It resembles concrete or gravel and is sold cheaply on the streets. In recent years, its impact has been limited to areas like the Gulf Coast, Georgia, and Ohio, but authorities around the nation are keeping a close eye on this drug and hoping to control the spread. The potential effects of heroin use, fentanyl ,carfentanil, and other opioid use are already highly dangerous and can result in death. Combining them creates the possibility of causing worse outcomes.

Consuming illicit opioids is dangerous in its own right, however combining them increases one’s risk of suffering one or more dangers, such as unknowingly consuming other substances. Many illicit opioids are being cut with more potent, powerful opioids like fentanyl in an effort for dealers to make a higher monetary profit. Unfortunately, it’s impossible to know what other substances may or may not be laced into certain drugs, making a person more vulnerable to experiencing negative side effects, including overdose, which can be fatal.

Dangers of Combining Alcohol and Benzodiazepines

Alcohol and benzodiazepines both have central nervous system depressant effects. Alcohol can compound some of the effects of benzos, and vice versa. That means that drugs like Xanax, Valium, or Klonopin can dangerously synergize some of the effects of alcohol.3 As both alcohol and benzodiazepines are associated with anterograde amnestic effects, the combined cognitive effects can make it easier to forget how many drinks you’ve had or how many pills you’ve taken. Consuming these two substances in excess increases the risk of severe respiratory depression and death.

Dangers of Combining Heroin and Cocaine

A lot of people mistakenly think this is a somewhat “safe” combination because the two drugs “cancel each other out” (think mixing alcohol with cocaine). But the truth is the combined effects of heroin and cocaine  just make it feel like they cancel one another out. It can become more difficult to “gauge” your magnitude of opioid or cocaine intoxication, which can more easily lead to accidental overdose.

How to Get Help for Substance Misuse

Whether you’re deep in the throes of substance abuse or haven’t crossed that line yet, the rules of science always apply. Don’t risk your life with lethal drug combinations; it’s never worth it. If you are afraid that you might cross the line, or already have, there are people are people out there who can help you. Call one of our admissions navigators at so they can provide the support and information you need to get on the path toward recovery. You can also check your insurance coverage online now.

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