Summary
- Alcohol and marijuana affect the brain differently but both impair judgment, coordination, and cognition—and combining them can compound these effects in dangerous ways.
- Mixing weed and alcohol increases the risk of serious outcomes including impaired brain function, poor academic performance, worsened mental health, substance use disorders, and impaired driving.
- The order of use matters—drinking alcohol before using marijuana can increase THC absorption, which raises the likelihood of nausea, disorientation, or panic.
- Avoiding simultaneous use helps reduce risk by improving decision-making, reducing overdose potential, and avoiding compounding side effects.
- Marijuana is not a proven treatment for alcohol withdrawal and may reduce the effectiveness of recovery efforts; always consult a healthcare provider before using it as a substitute for treatment.
Many people assume combining alcohol and marijuana is harmless—maybe even fun. But mixing these two substances, often called “crossfading,” can lead to dangerous side effects, unpredictable interactions, and long-term consequences for your brain and body.
Whether you’re curious about how they affect you separately or together, this guide breaks down everything you need to know about weed and alcohol—how they work, what happens when you combine them, and why staying safe often means avoiding using both at the same time.
Help for alcohol addiction is just a phone call away. Call our free 24/7 national hotline and connect with the support you need.
How Alcohol and Marijuana Affect Your Brain & Body
Both alcohol and marijuana are psychoactive substances that affect your central nervous system—but they do so in different ways.
Alcohol
Alcohol is a central nervous system depressant, which means it slows down brain activity and bodily functions. While small amounts can create a feeling of relaxation or lowered inhibition, larger amounts impair physical coordination, slow reaction times, and disrupt decision-making. These effects are especially dangerous when driving or operating machinery.
When alcohol enters your bloodstream, it begins to affect areas of the brain that control your emotions, behavior, and judgment. Over time—or with excessive drinking—alcohol also damages organs like the liver, heart, and brain.
According to data from the 2023 National Survey on Drug Use and Health (NSDUH), 28.9 million people ages 12 and older had AUD in the past year.
Click here to learn more about alcohol’s effects on your health.
Marijuana
Marijuana contains a psychoactive compound called THC (tetrahydrocannabinol), which interacts with the brain’s endocannabinoid system. This system plays a role in regulating mood, memory, appetite, and perception.
THC binds to cannabinoid receptors in the brain, producing a range of effects—from euphoria and relaxation to anxiety or confusion, depending on the dose and the individual.
Although marijuana is sometimes perceived as “safer” than other substances, it still has real physiological and psychological impacts—especially when used frequently or in high doses.
Some of marijuana’s health effects include:
- Short Term: intoxication, anxiety, fear, distrust, panic or hallucinations, physical side effects (nausea, vomiting, elevated heart rate, respiratory problems, etc.)
- Long Term: impaired lung health, mental health challenges, cardiovascular effects, gastrointestinal problems, and an increased risk of several cancers (especially in people who smoke marijuana instead of using it by other means)
According to the CDC, about 22-30% of marijuana users have cannabis use disorder (CUD)—and the risk is greater for people who use more of the drug.
What Happens When You Mix Alcohol & Weed?
When used together, the effects of marijuana and alcohol can compound in unexpected—and sometimes harmful—ways.
Combining these substances can intensify the effects of both. That might sound appealing, but it significantly increases your risk of harmful health outcomes, especially if you’re not used to either substance.
The Risks of Mixing Weed & Alcohol:
| Health or Behavioral Risk | Description |
| Altered Brain Function | Use of both substances is associated with changes in brain activity and potential neurocognitive impairments. |
| Decreased Academic Performance | Co-use correlates with poorer outcomes in educational settings, especially in young adults. |
| Poorer Mental Health and Cognition | Linked to increased risk of mental health issues (e.g., anxiety, depression) and reduced cognitive performance. |
| Driving Under the Influence | Co-use increases the likelihood of impaired driving, due to compounded motor and cognitive impairments. |
| Increased Risk of Substance Use Disorder | Individuals who use both substances are more likely to develop AUD, CUD, or both. |
Why Order Matters:
Studies suggest that when mixing these substances, the order you consume them in can affect the outcome. Using cannabis before drinking alcohol may slow the absorption of alcohol, while drinking alcohol before using marijuana increases THC absorption—making you feel higher than intended. This can amplify disorientation, nausea, or panic.
Why It’s Safer to Avoid Mixing Marijuana & Alcohol
Choosing to avoid combining weed and alcohol can protect your physical health and improve your mental clarity. Here’s what you gain:
- Reduced Risk of Overuse: It’s easier to monitor your limits when only using one substance.
- Better Decision-Making: You’re more likely to make safe, informed choices.
- Improved Physical Safety: Less risk of accidents, falls, or impaired driving.
- Fewer Negative Side Effects: You avoid unpleasant symptoms like vomiting, confusion, or paranoia.
If you are attempting to reduce your consumption of either substance, keeping weed and alcohol separate (or skipping them altogether) makes that journey easier and safer.
Can Marijuana Be Used to Manage Alcohol Withdrawal?
Some people have explored using marijuana to help with alcohol recovery, either by making withdrawal symptoms more tolerable or by serving as a substitute for alcohol use. However, there is no clear pattern currently suggesting that this is effective.
In fact, research suggests that any amount of cannabis use reduces the number of days people in alcohol treatment spend abstaining from alcohol—suggesting that it is not an effective way to manage withdrawal symptoms.
This approach also comes with all the same risks of mixing alcohol with marijuana (see chart above). While you may hear anecdotes suggesting that certain strains have been beneficial for specific users, it’s important to understand that drugs affect individuals differently—and no unprescribed drug, including marijuana, should ever be used as a substitute for medically supervised detox.
Bottom line: Don’t self-medicate. Talk to a healthcare provider before trying marijuana to treat alcohol withdrawal.
Know the Risks of Mixing Alcohol with Marijuana
Mixing alcohol and marijuana may be common, but that doesn’t make it safe. Crossfading can amplify the worst effects of both substances and increase the chances of harm. While some people experiment with marijuana during alcohol withdrawal, the safest path is always a medically guided one.
If you’re concerned about your use of either substance—or both—support is available. Alcohol Awareness can help you understand your options and take the next step towards a healthier lifestyle.
Need Help or Support?
If you or someone you love is struggling with alcohol or marijuana use, don’t wait. Call our 24/7 national hotline today. Our team can connect you to appropriate treatment providers, support groups, and other resources to help you move forward with confidence.