# data[].attributes.attachment_link.readable_text
What is polysubstance use?

The use of more than one drug, also known as polysubstance use, is common. This includes when two or more are taken together or within a short time period, either intentionally or unintentionally.

Intentional polysubstance use occurs when a person takes a drug to increase or decrease the effects of a different drug or wants to experience the effects of the combination.

Unintentional polysubstance use occurs when a person takes drugs that have been mixed or cut with other substances, like fentanyl, without their knowledge.

Whether intentional or not, mixing drugs is never safe because the effects from combining drugs may be stronger and more unpredictable than one drug alone, and even deadly.

What about prescription drugs?

The dangers of polysubstance use also apply to prescription drugs. Always let your doctor know what drugs you are taking to prevent any adverse reactions with newly prescribed medications. Never take pills that did not come from a pharmacy and weren't prescribed to you.

Get the facts

250+ -The number of American lives lost to drugs every day. ¹

50% - In 2019, nearly half of drug overdose deaths involved multiple drugs. ²

The dangers of polysubstance use

Examples of stimulants: ecstasy (MDMA), cocaine, methamphetamines, amphetamines (speed)

Stimulants (also known as uppers) can increase your heart rate and blood pressure to dangerous levels and increase your risk of several serious health problems. Combining stimulants may even directly or indirectly increase your risk of:

Brain injury

Liver damage

Heart attack

Stroke

Signs of use/overdose 3,4 that may occur when mixing stimulants:

Fast/troubled breathing

Increased body temperature

Nausea or vomiting

Chest pain

Seizures or tremors

Examples of depressants: opioids (heroin, morphine, oxycodone, hydrocodone, fentanyl), benzodiazepines

Depressants (also known as downers) can slow down your breathing and increase your risk of several adverse health outcomes. Combining depressants can also directly or indirectly increase your risk of:

Damage to the brain and other organs

Overdose

Death

Signs of use/overdose 5,6 when mixing depressants:

Slow breathing

Weak pulse

Altered mental status or confusion

Passing out

Mixing stimulants and depressants

Mixing stimulants and depressants doesn't balance or cancel them out. In fact, the results of combining drugs are unpredictable, often modifying or even masking the effects of one or both drugs. This may trick you into thinking that the drugs are not affecting you, making it easier to overdose.

Drinking alcohol while using other drugs

Drinking alcohol while using other drugs isn't safe. Alcohol is a depressant with similar effects to other downers. Mixing alcohol with other drugs can increase your risk of overdose and serious damage to the brain, heart, and other organs.

What to do if you think someone is overdosing

It may be hard to tell whether a person is high or experiencing an overdose. If you aren't sure, treat it like an overdose-you could save a life.

Call 911 Immediately.*

Administer naloxone, if available. **

Try to keep the person awake and breathing.

Lay the person on their side to prevent choking.

Stay with the person until emergency assistance arrives.

*Most states have laws that may protect a person who is overdosing or the person who called for help from legal trouble. **Naloxone is a life-saving medication that can reverse the effects of opioid overdose and save lives. It is available in all 50 states and can be purchased from a local pharmacy without a prescription in most states.

Understanding the risks of mixing drugs (:30)

Understanding the risks of mixing drugs (:60)

Protect yourself from the dangers of fentanyl (:30)

Protect yourself from the dangers of fentanyl (:60)

Protect friends and family with lifesaving naloxone (:60)

1. NCHS, National Vital Statistics System. Estimates for 2020 are based on provisional data. Estimates for 2015-2019 are based on final data (available from: https://www.cdc.gov/nchs/nvss/vsrr/drug-overdose-data.htm).

2. O'Donnell J, Gladden RM, Mattson CL, Hunter CT, Davis NL. Vital Signs: Characteristics of Drug Overdose Deaths Involving Opioids and Stimulants - 24 States and the District of Columbia, January-June 2019. MMWR Morb Mortal Wkly Rep 2020; 69:1189-1197. DOI: http://dx.doi.org/10.15585/mmwr.mm6935a1

3. NIDA. 2020, October 7. Cocaine. Retrieved from https://teens.drugabuse.gov/drug-facts/cocaine on 2021, March 11

4. NIDA. 2019, May 16. Methamphetamine DrugFacts. Retrieved from https://www.drugabuse.gov/publications/drugfacts/methamphetamine on 2021, March 11

5. SAMHSA. 2020, August 19. Opioid Overdose. Retrieved from https://www.samhsa.gov/medication-assisted-treatment/medications-counseling-related-conditions/opioid-overdose

6. National Institute on Drug Abuse. (n.d.). Heroin (smack, junk) facts. Easy-to-Read Drug Facts. Retrieved from https://easyread.drugabuse.gov/content/effects-heroin-brains-and-bodies

Page last reviewed:

# data[].attributes.attachment_link.keywords[]
polysubstance use; mixing drugs; multiple drugs; uppers; downers; stimulants; depressants; drug overdose

# data[].attributes.attachment_link.description
An overview of the risks of using more than one drug together.

# data[].attributes.attachment_link.readable_text
What is Polysubstance Use?

Polydrug use involves the consumption of more than one drug at once. Although polysubstance misuse often refers to Misuse of multiple illicit drugs, it's also inclusive of prescription medications used in nonmedical circumstances.

Polysubstance misuse may also be referred to as: polysubstance abuse and polysubstance addiction

In some instances, those on prescription medication may unintentionally combine substances. They may have a few glasses of wine without realizing that their prescription medication should not be mixed with alcohol, or they may be on multiple prescriptions from different doctors, not realizing that these medications interact negatively with one another. As a result, individuals should always inform every doctor of every medication they are taking and confirm that medications don't interact negatively with each other or alcohol prior to beginning a new prescription.

Other people intentionally engage in polysubstance miuse in an effort to experience greater effects from multiple substances. Oftentimes, users may have a preferred substance of misuse that they then combine with other substances at times to enhance the primary substance's effects. For example, those who regularly misuse opioid drugs, like heroin or prescription painkillers, may sometimes take them with benzodiazepines to experience even greater relaxation or sedative effects.

While the combination of certain substances can certainly enhance desired effects of the drugs, polysubstance misuse also enhances the potential negative effects of each drug.

According to the University of Michigan, mixing drugs can also bring unpredictable consequences; this means that those who engage in polysubstance misuse cannot predict the array and severity of negative consequences that could result.

Take Our Substance Misuse Self-Assessment

Take our free, 5-minute substance misuse self-assessment below if you think you or someone you love might be struggling with substance misuse. The evaluation consists of 11 yes or no questions that are intended to be used as an informational tool to assess the severity and probability of a substance use disorder. The test is free, confidential, and no personal information is needed to receive the result.

Dangers Associated with Polysubstance Misuse

Specific short-term and long-term effects related to polysubstance misuse will differ according to the particular combination of substances; however, there are some general dangers associated with polysubstance misuse. These include:

Increased severity of side effects: All drugs come with the potential for negative side effects. When substances are misused together, the potential severity of these side effects is increased exponentially. It isn't as simple as adding up the separate effects of each substance; instead, the substances combine to cause addictive effects, and these effects are often unique and more severe than the separate effects of each drug. General side effects from polysubstance misuse may include nausea, vomiting, body pain, balance issues, and changes to heart rate, respiration rate, and blood pressure.

Acute health problems: Drug interactions can reduce metabolism, increasing blood concentrations of the substances in question. Per the European Monitoring Centre for Drugs and Drug Addiction (EMCDDA), this boosts toxicity and can produce new metabolites formed from the breakdown of multiple substances. Various diseases and disorders are more common in those who misuse multiple substances. For example, chronic diseases, such as hepatitis C, are often seen in heavy drinkers who inject drugs, and tobacco smokers who use cocaine are more at risk for myocardial infarction, EMCDDA reports.

Complications due to co-occurring mental health issues: Those who suffer from cases of co-occurring disorders, when a substance use disorder occurs alongside another mental health disorder, may be more likely to engage in polysubstance misuse. Substance misuse often worsens the symptoms of the mental health disorder, and likewise, the mental health issue can lead to worsened substance misuse. When multiple substances are misused, all these effects are amplified.

Polysubstance Overdose

While overdose is always a possibility with any kind of substance misuse, its risk is heightened when multiple substances are misused. Since certain substances mask the effects of other substances, users may inadvertently take far higher doses than they normally would because they don't feel the full effects of one substance. As a result, overdose may occur. With overdose, long-term health effects are always possible, as is death.

Overdose from multiple substances of misuse is more difficult to treat. While opioid overdose can often be reversed with the prompt use of naloxone, it may not be effective if the overdose is due to other substances of misuse as well, such as benzodiazepines, stimulants, or alcohol. In addition, polysubstance addiction ( cross addiction) generally requires more specialized treatment to achieve full recovery.

Specific Substance Combinations

As with other substances, alcohol is commonly combined with both prescription and illicit drugs in an effort to achieve a "better" or "stronger" high, or in an effort to counteract the effects of certain substances. For example, a person may take a stimulant like cocaine to counteract the depressant qualities of alcohol, allowing the person to drink more for longer periods of time.

A University of Michigan study found that reports of prescription drug misuse were 18 times higher in participants who were dependent on alcohol.

According to NIDA, simultaneous use of alcohol and prescription drugs can result in alcohol poisoning, blackouts, respiratory depression, and death. Alcohol is often mixed with prescription opiates, such as Vicodin, Percocet, and OxyContin, and it is also commonly combined with stimulants, such as Ritalin, and sedatives or anti-anxiety medications, including Xanax and Valium. It's also common for people to take sleeping medications with alcohol in an effort to fall asleep even more quickly.

Consuming alcohol with prescription medications can lead to dangerous interactions, as certain drugs can alter the effects of alcohol in the body. In some instances, individuals may drink far more due to the interaction of drugs and end up with much higher blood alcohol concentrations as a result. Mixing alcohol and drugs therefore raises the risk of alcohol poisoning and potentially life-threatening consequences.

Cocaine and alcohol

These two substances are commonly combined. When a cocaine user drinks alcohol, the amount of cocaine in their system can increase by 30 percent. A psychoactive metabolite, cocaethylene, is produced that stays in the blood for longer, and heart rate and blood pressure increase, which can lead to cardiovascular problems. A person may also consume more alcohol because cocaine may reduce the perception of alcohol's effects.
Opioids and cocaine These drugs have opposing effects. The central nervous system is depressed by opioids and stimulated by cocaine. As with cocaine and alcohol, users may attempt to take these substances together in an effort to counteract negative effects of either drug. For example, users may be amped up from cocaine and take opioids in an effort to calm the body and induce sleep. Since these substances can mask the effects of each other, overdose and other potential complications are more likely.

Opioids and benzodiazepines

All three of these substances are central nervous system depressants. As a result, combining them can quickly result in respiratory depression that can lead to fatal overdose. Restricted oxygen flow to the brain can cause permanent damage and impairment or death. In addition, benzodiazepines are not metabolized as quickly by older drug users, and this increases the risk of respiratory complications.

In a 2014 report, the Substance Abuse and Mental Health Services Administration (SAMHSA) stated that close to 1 million emergency department visits from 2005 to 2011 involved benzodiazepines, or a combination of benzodiazepines and alcohol or opioid pain relief medications. They also found a 24-55 percent increase in predicted risk of serious outcomes from combining the drugs compared to using only benzodiazepines. When it comes to fatalities related to benzodiazepine use, they most often occur when the drugs are mixed with other substances of misuse.

Prescription and illicit drugs

Though some people believe that prescription drugs are "safer" to misuse than illicit drugs since they are originally prescribed by a doctor, this is not true. Many prescription drugs are not that different in formulation to illicit drugs, and their misuse can result in a range of serious health outcomes, up to and including death. Polysubstance misuse that involves prescription drugs is no less dangerous than such misuse that involves illicit or "street" drugs. This misuse may include combining prescription drugs with alcohol, other prescription drugs, or illicit drugs.

Polysubstance misuse that involves any type of prescription drug, even cold and cough medicines, can have severe consequences. The cough suppressant dextromethorphan (DXM) can cause hallucinations at high doses, and promethazine-codeine cough syrup has an antihistamine that induces sedative effects. Per NIDA, these medications are often misused in combination with alcohol or marijuana.

How Detox Works in Cases of Polysubstance Misuse

Since withdrawal from multiple substances is more complicated than withdrawal from one substance, inpatient medical detox is generally recommended.

With medical detox, clients are supervised 24 hours per day by medical professionals. This ensures continual monitoring of vital signs, and prompt action should any medical emergencies occur. In addition, supervising physicians often administer medications to counteract certain withdrawal symptoms, such as anti-nausea medications to deal with vomiting and intestinal upset or antidepressants to address mood fluctuations.

In certain instances of substance misuse, long-term maintenance medications may be administered. For example, if a person was regularly abusing prescription painkillers like Vicodin and cocaine, medical staff may administer an opioid replacement medication, such as methadone or buprenorphine, to mitigate the severity of opioid withdrawal. Since cocaine withdrawal symptoms don't tend to be as intense, the symptoms of cocaine withdrawal may simply be monitored and medicated as needed. In other instances, such as with benzodiazepine withdrawal, a tapering approach may be implemented, in which the dosage of a long-acting benzodiazepine may be slowly lowered over time, gradually easing the client off the drug to lessen the severity of withdrawal.

Due to the potential unpredictability of withdrawal from multiple substances, continual medical monitoring is always needed. In addition, the support and encouragement available in medical detox decreases the likelihood of relapse and increases the chances of successful withdrawal from all substances of misuse.

Comprehensive Treatment for Polysubstance Misuse

While detox is a critical first step in the recovery process, it is not effective treatment on its own. It must be followed by a comprehensive addiction treatment program that primarily includes therapy.

In all cases of substance use disorders, including those involving polysubstance misuse, Cognitive Behavioral Therapy (CBT) is often used. This therapy focuses on the behavioral and thought patterns involved in substance misuse, helping to modify thoughts and thereby change behaviors. According to Psychology Today, CBT can be effective in altering destructive behavioral patterns, such as those involved in substance misuse.

The key with any substance misuse treatment program is that care is tailored to the individual needs of each client. There is no one-size-fits-all solution that will work for everyone. Per NIDA, the most effective treatment programs will customize treatment to address all of the person's needs, not just those related to their substance misuse. In cases of polysubstance misuse, this entails identifying the reasons that led to the desire to misuse any substance and then dealing with those issues appropriately.

Oftentimes, treatment plans will need to be restructured throughout the recovery process. As a person progresses in recovery, various alterations may need to be made, and if a particular therapy isn't proving effective, a new one can be tried in its place.

Any co-occurring mental health issues should be identified early in treatment, often during an initial assessment. This ensures that the entire person will be effectively cared for, rather than just the substance misuse issue. With comprehensive care, those engaging in polysubstance misuse can leave misuse of all substances in their past as they embrace a healthier future in recovery.

# data[].attributes.attachment_link.title
Polysubstance Use & Misuse: The Unique Treatment Needs of Polydrug Users

# data[].attributes.attachment_link.description
Polydrug use involves the consumption of more than one drug at once. Although polysubstance misuse often refers to Misuse of multiple illicit drugs, it's also inclusive of prescription medications used in nonmedical circumstances. Polysubstance misuse may also be referred to as: polysubstance abuse and polysubstance addiction In some instances, those on prescription medication may unintentionally combine substances.

# data[].attributes.attachment_link.description
As the nation’s health protection agency, CDC saves lives and protects people from health, safety, and security threats.

# data[].attributes.attachment_link.readable_text
What are some signs of an opioid overdose?

unconsciousness

very small pupils

slow or shallow breathing

vomiting

an inability to speak

faint heartbeat

limp arms and legs

pale skin

purple lips and fingernails

What is naloxone?

Naloxone is a medicine that rapidly reverses an opioid overdose. It is an opioid antagonist. This means that it attaches to opioid receptors and reverses and blocks the effects of other opioids. Naloxone can quickly restore normal breathing to a person if their breathing has slowed or stopped because of an opioid overdose. But, naloxone has no effect on someone who does not have opioids in their system, and it is not a treatment for opioid use disorder. Examples of opioids include heroin, fentanyl, oxycodone (OxyContin ®), hydrocodone (Vicodin ®), codeine, and morphine.

How is naloxone given?

Naloxone should be given to any person who shows signs of an opioid overdose or when an overdose is suspected. Naloxone can be given as a nasal spray or it can be injected into the muscle, under the skin, or into the veins. Steps for responding to an opioid overdose can be found in the Substance Abuse and Mental Health Administration's (SAMHSA) Opioid Overdose Prevention Toolkit.

First Responders Can Safely Administer Naloxone during the COVID-19 Pandemic (HHS)

What are the different naloxone delivery systems?

Naloxone comes in two FDA-approved forms: injectable and prepackaged nasal spray. No matter what dosage form you use, it's important to receive training on how and when to use naloxone. You should also read the product instructions and check the expiration date.

Injectable brands of naloxone are offered by different companies listed in the FDA Orange Book under "naloxone" (look for "injectable"). Typically, the proper dose must be drawn up from a vial. Usually, it is injected with a needle into muscle, although it also may be administered into a vein or under the skin. The FDA recently approved , a single-dose, prefilled syringe that can be injected into the muscle or under the skin.
Note: Some people use an improvised nasal spray emergency kit not approved by the FDA that combines injectable naloxone with an attachment designed to deliver naloxone through the nose. However, this improvised intranasal device is not easy to assemble, especially when under pressure in an emergency, and requires training beforehand. Additionally, the FDA-approved naloxone devices have been shown to produce substantially higher blood levels of naloxone than the improvised nasal spray. These outcomes suggest that the approved prepackaged nasal spray technology is preferable over non-FDA-approved forms.

Prepackaged Nasal Spray (generic naloxone, Narcan, Kloxxado), developed as a result of NIDA-funded research, is an FDA-approved prefilled, needle-free device that requires no assembly and is sprayed into one nostril while the person lays on their back. This device can also be easier for loved ones and bystanders without formal training to use.

Is Narcan® the same as naloxone?

When naloxone was first approved to reverse opioid overdoses, its brand name was "Narcan." There are now other formulations and brand names for naloxone, but many people continue to call all of these products "Narcan." However, the proper generic name is "naloxone."

Is there a preferable delivery system?

All systems used by first responders deliver the stated dose of naloxone and can be highly effective in reversing an opioid overdose. Study findings released in March 2019 suggests that the FDA-approved naloxone devices deliver higher blood levels of naloxone than the improvised nasal devices.

Can I give naloxone to someone who has overdosed?

Yes. Families with loved ones who struggle with opioid addiction should have naloxone nearby; ask their family member to carry it; and let friends know where it is. People should still call 911 immediately in the event of an overdose.

Naloxone is being used more by police officers, emergency medical technicians, and non-emergency first responders than before. In most states, people who are at risk or who know someone at risk for an opioid overdose can be trained on how to give naloxone. Families can ask their pharmacists or health care provider how to use the devices.

What precautions are needed when giving naloxone?

Naloxone works to reverse opioid overdose in the body for only 30 to 90 minutes. But many opioids remain in the body longer than that. Because of this, it is possible for a person to still experience the effects of an overdose after a dose of naloxone wears off. Also, some opioids are stronger and might require multiple doses of naloxone. Therefore, one of the most important steps to take is to call 911 so the individual can receive immediate medical attention. NIDA is supporting research for stronger formulations for use with potent opioids like fentanyl.

People who are given naloxone should be observed constantly until emergency care arrives. They should be monitored for another 2 hours after the last dose of naloxone is given to make sure breathing does not slow or stop.

Tolerance vs. Dependence vs. Addiction

Long-term use of prescription opioids, even as prescribed by a doctor, can cause some people to develop a tolerance, which means that they need higher and/or more frequent doses of the drug to get the desired effects.

Drug dependence occurs with repeated use, causing the neurons to adapt so they only function normally in the presence of the drug. The absence of the drug causes several physiological reactions, ranging from mild in the case of caffeine, to potentially life-threatening, such as with heroin. Some chronic pain patients are dependent on opioids and require medical support to stop taking the drug.

Drug addiction is a chronic disease characterized by compulsive, or uncontrollable, drug seeking and use despite harmful consequences and long-lasting changes in the brain. The changes can result in harmful behaviors by those who misuse drugs, whether prescription or illicit drugs.

People with physical dependence on opioids may have withdrawal symptoms within minutes after they are given naloxone. Withdrawal symptoms might include headaches, changes in blood pressure, rapid heart rate, sweating, nausea, vomiting, and tremors. While this is uncomfortable, it is usually not life threatening. The risk of death for someone overdosing on opioids is worse than the risk of having a bad reaction to naloxone. Clinicians in emergency room settings are being trained to offer patients immediate relief and referral to treatment for opioid use disorder with effective medications after an opioid overdose is reversed. NIDA offers tools for emergency clinicians here.

Side effects from naloxone are rare, but people might have allergic reactions to the medicine. Overall, naloxone is a safe medicine. But it only reverses an overdose in people with opioids in their systems and will not reverse overdoses from other drugs like cocaine or methamphetamine.

How much does naloxone cost?

The cost varies depending on where you get the naloxone, how you get it, and what type you get. Patients with insurance should check with their insurance company to see if this medicine is covered. Patients without insurance can check the retail costs at their local pharmacies. Some drug companies have cost assistance programs for patients unable to pay for it.

Where can I get naloxone?

Many pharmacies carry naloxone. In some states, you can get naloxone from a pharmacist even if your doctor did not write you a prescription for it. It is also possible to get naloxone from community-based distribution programs, local public health groups, or local health departments, free of charge.

Co-Prescribing Naloxone with Prescription Opioids

Research indicates that clinicians prescribing naloxone along with prescription opioids may reduce the risk of opioid-related emergency room visits and prescription opioid-involved overdose deaths. The U.S. Centers for Disease Control and Prevention recommends co-prescription of naloxone for some patients who take opioids. This recommendation was first outlined in the 2016 CDC Guideline for Prescribing Opioids for Chronic Pain and is still present in the updated 2022 CDC Clinical Practice Guideline for Prescribing Opioids for Pain.

Points to remember

Naloxone is a medicine that rapidly reverses an opioid overdose. It attaches to opioid receptors and reverses and blocks the effects of other opioids.

Naloxone is a safe medicine. It only reverses overdoses in people with opioids in their systems.

There are two FDA-approved formulations of naloxone: injectable and prepackaged nasal spray.

Police officers, emergency medical technicians, and first responders are trained on how to give naloxone.

In some states, friends and family members can be trained on how to give naloxone.

Naloxone only works in the body for 30 to 90 minutes. It is possible for a person to still experience the effects of an overdose after naloxone wears off or need multiple doses if a potent opioid is in a person's system.

In some areas, you can get naloxone from pharmacies with or without a personal prescription from community-based distribution programs, or local health departments. The cost varies depending on where and how you get it as well as what type you get.

Learn more

For more information about naloxone and opioid use disorder, visit:

# data[].attributes.attachment_link.title
Naloxone DrugFacts | National Institute on Drug Abuse

# data[].attributes.attachment_link.description
Naloxone can quickly restore normal breathing to a person during an opioid overdose.

# data[].attributes.attachment_link.readable_text
Panel 1
What is Drugged Driving? Driving while under the influence of legal or illegal substances. It puts the driver, passengers, and others who share the road in danger. It is illegal in every state.

Panel 2
How Common is Drugged Driving?

Panel 2, Figure 1
In 2017, among people of ages 16 or older... ¹

21.4 million drove after drinking alcohol.

12.8 million drove after using illicit drugs.*

Panel 2, Figure 2
In 2016, among people killed in driving accidents... ²

43.6% of drivers who were drug tested and had positive results.

50.5% were positive for two or more drugs

40.7 % were positive for alcohol.

* illicit drugs = marijuana, cocaine (including crack), heroin, hallucinogens, inhalants, or methamphetamine.

Panel 3
What are effects of Drugs on Driving?

Driving under the influence of drugs affects you and everyone around you.

Effects of Drugs on Driving

Marijuana-slows reaction time and impairs judgment of time and distance

Methamphetamine or Cocaine-aggressive and reckless behaviors

Opioids-drowsiness and impaired memory and thinking skills

Sedatives (benzodiazepines, barbiturates, etc.)-dizziness and drowsiness

Panel 4
What are Some Strategies to Prevent Drugged Driving

Offer to be a designated driver.

Have a designated driver take all car keys.

Get a ride to and from parties where there are drugs and alcohol.

Avoid going to parties where alcohol and drugs are present.

Talk with friends about the risks of drugged driving.

For more information, visit NIDA's Drugged Driving DrugFacts at drugabuse.gov/publications/drugfacts/drugged-driving.
References

1. Substance Abuse and Mental Health Services Administration. Results from the 2017 National Survey on Drug Use and Health: Detailed Tables. https://www.samhsa.gov/data/sites/default/files/cbhsq-reports/NSDUHDetailedTabs2017/NSDUHDetailedTabs2017.htm#tab6-84A. Accessed September 24, 2018.

2. Governors Highway Safety Association. Drug-Impaired Driving: Marijuana and Opioids Raise Critical Issues for States | GHSA. https://www.ghsa.org/resources/DUID18. Accessed August 20, 2018.

# data[].attributes.attachment_link.title
Drugged Driving Infographic | National Institute on Drug Abuse

# data[].attributes.attachment_link.description
Panel 1 What is Drugged Driving? Driving while under the influence of legal or illegal substances. It puts the driver, passengers, and others who share the road in danger. It is illegal in every state. Panel 2 How Common is Drugged Driving? Panel 2, Figure 1 In 2017, among people of ages 16 or older...

# data[].attributes.attachment_link.readable_text
Drugged driving is driving a vehicle while impaired due to the intoxicating effects of recent drug use. It can make driving a car unsafe-just like driving after drinking alcohol. Drugged driving puts the driver, passengers, and others who share the road at serious risk.

Why is drugged driving dangerous?

The effects of specific drugs on driving skills differ depending on how they act in the brain. For example, marijuana can slow reaction time, impair judgment of time and distance, and decrease coordination. Drivers who have used cocaine or methamphetamine can be aggressive and reckless when driving. Certain kinds of prescription medicines, including benzodiazepines and opioids, can cause drowsiness, dizziness, and impair cognitive functioning (thinking and judgment). All of these effects can lead to vehicle crashes.

Research studies have shown negative effects of marijuana on drivers, including an increase in lane weaving, poor reaction time, and altered attention to the road. Use of alcohol with marijuana makes drivers more impaired, causing even more lane weaving. Some studies report that opioids can cause drowsiness and impair thinking and judgment. Other studies have found that being under the influence opioids while driving can double your risk of having a crash.

It is difficult to determine how specific drugs affect driving because people tend to mix various substances, including alcohol. But we do know that even small amounts of some drugs can have a measurable effect. As a result, some states have zero-tolerance laws for drugged driving. This means a person can face charges for driving under the influence (DUI) if there is any amount of drug in the blood or urine. Many states are waiting to develop laws until research can better define blood levels that indicate impairment, such as those they use with alcohol.

Read more about other commonly misused drugs that can effect driving.

How many people take drugs and drive?

According to the 2021 National Survey on Drug Use and Health (NSDUH), in 2021, 13.5 million people aged 16 or older drove under the influence of alcohol in the past year and 11.7 million drove under the influence of selected illicit drugs, including marijuana (2021 DT 8.33A).

The survey also showed that men are more likely than women to drive under the influence of drugs or alcohol. A higher percentage of adults aged 21 to 25 (15.0%) drive after taking drugs or drinking than do young adults aged 16 to 20 (7.5%) or adults 26 or older (7.7%) (2021 DT 8.33B).

Which drugs are linked to drugged driving?

After alcohol, marijuana is the drug most often found in the blood of drivers involved in crashes. Tests for detecting marijuana in drivers measure the level of delta-9-tetrahydrocannabinol (THC), marijuana's mind-altering ingredient, in the blood. But the role that marijuana plays in crashes is often unclear. THC can be detected in body fluids for days or even weeks after use, and it is often combined with alcohol. The vehicle crash risk associated with marijuana in combination with alcohol, cocaine, or benzodiazepines appears to be greater than that for each drug by itself.

Several studies have shown that drivers with THC in their blood were roughly twice as likely to be responsible for a deadly crash or be killed than drivers who hadn't used drugs or alcohol. However, a large NHTSA study found no significant increased crash risk traceable to marijuana after controlling for drivers' age, gender, race, and presence of alcohol. More research is needed.

Along with marijuana, prescription drugs are also commonly linked to drugged driving crashes. In 2016, 19.7 percent of drivers who drove while under the influence tested positive for some type of opioid.

How often does drugged driving cause crashes?

It's hard to measure how many crashes are caused by drugged driving. This is because:

a good roadside test for drug levels in the body doesn't yet exist

some drugs can stay in your system for days or weeks after use, making it difficult to determine when the drug was used, and therefore, how and if it impaired driving

police don't usually test for drugs if drivers have reached an illegal blood alcohol level because there's already enough evidence for a DUI charge

many drivers who cause crashes are found to have both drugs and alcohol or more than one drug in their system, making it hard to know which substance had the greater effect

Effects of Commonly Misused Drugs on Driving

Marijuana affects psychomotor skills and cognitive functions critical to driving including vigilance, drowsiness, time and distance perception, reaction time, divided attention, lane tracking, coordination, and balance.

Opioids can cause drowsiness and can impair cognitive function.

Alcohol can reduce coordination, concentration, ability to track moving objects and reduce response to emergency driving situations as well as difficulty steering and maintaining lane position. It can also cause drowsiness.

However, according to the Governors Highway Safety Association, 43.6 percent of fatally injured drivers in 2016 tested positive for drugs and over half of those drivers were positive for two or more drugs.

What populations are especially affected by drugged driving?

Teen and older adult drivers are most often affected by drugged driving. Teens are less experienced and are more likely than other drivers to underestimate or not recognize dangerous situations. They are also more likely to speed and allow less distance between vehicles. When lack of driving experience is combined with drug use, the results can be tragic. Car crashes are the leading cause of death among young people aged 16 to 19 years.

A study of college students with access to a car found that 1 in 6 had driven under the influence of a drug other than alcohol at least once in the past year. Marijuana was the most common drug used, followed by cocaine and prescription pain relievers.

Mental decline in older adults can lead to taking a prescription drug more or less often than they should or in the wrong amount. Older adults also may not break down the drug in their system as quickly as younger people. These factors can lead to unintended intoxication while behind the wheel of a car.

What steps can people take to prevent drugged driving?

Because drugged driving puts people at a higher risk for crashes, public health experts urge people who use drugs and alcohol to develop social strategies to prevent them from getting behind the wheel of a car while impaired. Steps people can take include:

offering to be a designated driver

appointing a designated driver to take all car keys

getting a ride to and from parties where there are alcohol and/or drugs.

discussing the risks of drugged driving with friends in advance

Points to Remember

Use of illicit drugs or misuse of prescription drugs can make driving a car unsafe-just like driving after drinking alcohol.

In 2018, 20.5 million people aged 16 or older drove under the influence of alcohol in the past year and 12.6 million drove under the influence of illicit drugs.

It's hard to measure how many crashes are caused by drugged driving, but estimates show that almost 44 percent of drivers in fatal car crashes tested positive for drugs.

Driving under the influence of marijuana, opioids and alcohol can have profound effects on driving.

People who use drugs and alcohol should develop social strategies to prevent them from getting behind the wheel of a car while impaired.

Learn More

For more information about drugged driving webpage.

For more information about marijuana and prescription drug misuse, visit:

*The COVID-19 pandemic had an impact on data collection for the 2021 National Survey on Drug Use and Health (NSDUH). For more information, please see the 2021 NSDUH Frequently Asked Questions from the Substance Abuse and Mental Health Services Administration.

References

1. Hartman RL, Huestis MA. Cannabis effects on driving skills. Clin Chem. 2013;59(3):478-492. doi:10.1373/clinchem.2012.194381

2. Hartman RL, Brown TL, Milavetz G, et al. Cannabis effects on driving lateral control with and without alcohol. Drug Alcohol Depend. 2015;154:25-37. doi:10.1016/j.drugalcdep.2015.06.015

3. Lenné MG, Dietze PM, Triggs TJ, Walmsley S, Murphy B, Redman JR. The effects of cannabis and alcohol on simulated arterial driving: Influences of driving experience and task demand. Accid Anal Prev. 2010;42(3):859-866. doi:10.1016/j.aap.2009.04.021

4. Compton R. Marijuana-Impaired Driving: A Report to Congress. Washington, DC: National Highway Traffic Safety Administration; 2017.

5. Dhingra L, Ahmed E, Shin J, Scharaga E, Magun M. Cognitive Effects and Sedation. Pain Med Malden Mass. 2015;16 Suppl 1:S37-S43. doi:10.1111/pme.12912

6. Chihuri S, Li G. Use of prescription opioids and motor vehicle crashes: A meta analysis. Accid Anal Prev. 2017;109:123-131. doi:10.1016/j.aap.2017.10.004

7. Substance Abuse Center for Behavioral Health Statistics and Quality. Results from the 2021 National Survey on Drug Use and Health: Detailed Tables, SAMHSA. Accessed January 2023.

8. Wilson FA, Stimpson JP, Pagán JA. Fatal crashes from drivers testing positive for drugs in the U.S., 1993-2010. Public Health Rep Wash DC 1974. 2014;129(4):342-350.

9. Biecheler M-B, Peytavin J-F, Facy F, Martineau H. SAM survey on "drugs and fatal accidents": search of substances consumed and comparison between drivers involved under the influence of alcohol or cannabis. Traffic Inj Prev. 2008;9(1):11-21. doi:10.1080/15389580701737561

10. Elvik R. Risk of road accident associated with the use of drugs: a systematic review and meta-analysis of evidence from epidemiological studies. Accid Anal Prev. 2013;60:254-267. doi:10.1016/j.aap.2012.06.017

11. Compton RP, Berning A. Drug and Alcohol Crash Risk. Washington, DC: National Highway Traffic Safety Administration; 2015. DOT HA 812 117.

12. Fatality Analysis Reporting System (FARS). Washington, DC: National Highway Traffic Safety Administration https://www.nhtsa.gov/research-data/fatality-analysis-reporting-system-fars.

13. Drug-Impaired Driving: Marijuana and Opioids Raise Critical Issues for States. Washington DC: Governors Highway Safety Association; 2018.

14. Teen Drivers: Get the Facts | Motor Vehicle Safety | CDC Injury Center. http://www.cdc.gov/motorvehiclesafety/teen_drivers/teendrivers_factsheet.html. Published October 14, 2015. Accessed April 7, 2016.

15. Arria AM, Caldeira KM, Vincent KB, Garnier-Dykstra LM, O'Grady KE. Substance-related traffic-risk behaviors among college students. Drug Alcohol Depend. 2011;118(2-3):306-312. doi:10.1016/j.drugalcdep.2011.04.012

# data[].attributes.attachment_link.title
Drugged Driving DrugFacts | National Institute on Drug Abuse

# data[].attributes.attachment_link.description
Provides basic facts about drugged driving, including statistics, trends, and teen prevalence, and explains why drugged driving is hazardous, particularly as it relates to marijuana.

# data[].attributes.attachment_link.description
An official website of the State of Maryland.

# data[].attributes.attachment_link.title
Maryland Department of Health Good Samaritan Law

# data[].attributes.attachment_link.description
An official website of the State of Maryland.

# data[].attributes.attachment_link.readable_text
Take high doses of opioids for long-term management of chronic pain

Receive rotating opioid medication regimens

Have been discharged from emergency medical care following opioid poisoning or intoxication

Take certain extended-release or long-acting opioid medication

Those who have had a period of abstinence to include those recently released from incarceration.

Pregnant women can be safely given naloxone in limited doses under the supervision of a doctor.

A doctor or pharmacist can show patients, their family members, or caregivers how to administer naloxone.

Patients given an automatic injection device or nasal spray should keep the item available at all times. It is important to remember to replace medication when the expiration date passes and if exposed to temperatures below 39°F or above 104°F.

# data[].attributes.attachment_link.description
Take high doses of opioids for long-term management of chronic pain Receive rotating opioid medication regimens Have been discharged from emergency medical care following opioid poisoning or intoxication Take certain extended-release or long-acting opioid medication Those who have had a period of abstinence to include those recently released from incarceration.