Mixing alcohol, marijuana, prescription medications, and other drugs is dangerous. It’s difficult to predict the exact effects because each person reacts to these substances differently. Studies show that youth are more likely to abuse alcohol, marijuana, prescription medications, and other drugs than adults, and that they are also more likely to use more than one substance at a time. The adolescent brain is often likened to a car with a fully functioning gas pedal (the reward system) but weak brakes (the prefrontal cortex), which is why it is so susceptible to substance use and sometimes using multiple substances. It is important for parents and caregivers to talk with kids about the dangers of using substances and also combining them.

Also, studies have found a connection between youth use of alcohol and tobacco, and use of illicit drugs. Of the youth who reported heavy drinking (five or more drinks on the same occasion on each of five or more days in the past 30 days), 69.9 percent also reported using an illicit drug. In comparison, illicit drug use for those who were NOT current alcohol users was reported at 5.2 percent. Youth who smoke tobacco are nine times more likely to meet the medical criteria for alcohol abuse and 13 times more likely to meet the medical criteria for illicit drug abuse and dependence. Research suggests that nicotine can cause structural and chemical changes in teenage brains, increasing the risk of alcohol, marijuana, and opioid use.