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Monday March 27, 2017

By Morgan Smith


You’re out with friends, putting back a few drinks and someone asks if you want to head outside for a smoke sesh. It’s a scenario you’ve likely been—or taken part—in. But do you really know what happens when you combine the two? Learning about the science behind combining cannabis and alcohol will allow you to avoid greening out and have a pleasant experience.

There is an undeniable crossover between the cannabis and alcohol industries. Alone, they have their own effects on your brain, mind and behavior. When you smoke marijuana, THC—the main cannabinoid found in marijuana—interacts with your natural cannabinoid system to create psychoactive, yet relaxing qualities. Alcohol, on the other hand, is a depressant, affects the nervous system and impacts motor skills.

You might think that “crossfading”—or using alcohol and marijuana together—will simply cause these effects to combine. But things are a bit more complicated than that.

If you’ve taken part in the practice, you may have experienced an elevated high. And if you keep reading you’ll find out why. But you may have taken it too far and felt a side effect, known as greening out. It’s much more likely to occur when a person drinks a bit too much before smoking where the user experiences dizziness and nausea with a tendency to go pale, get sweaty and start vomiting.

But the same may not necessarily happen when you smoke before drinking. Let’s look to the scientific community to learn more.

What Science Says About Greening Out

We’re familiar with the effects of alcohol on the brain, but not much research has been done on cannabis, let alone what happens when we mix the two to the point of greening out. Part of that is because of marijuana’s classification as a Schedule I drug, which prohibits proper research from happening.

But Harvard Medical School Professor Scott Lukas has started to lay the groundwork by conducting the two most prominent studies examining what happens when we mix alcohol and weed. In 1992, Lukas looked at how smoking weed affects the absorption of alcohol. And in 2001, he looked at the flip side: how drinking alcohol affects the absorption of THC.

Both studies tested a small sample of male volunteers who were assigned one of three marijuana doses (placebo, low or moderate dosage) who drank various doses of ethanol on three separate days. In the most recent research, Lukas found that individuals who consumed cannabis, drank and then smoked detected more marijuana effects quicker, reported higher senses of euphoria and revealed higher THC levels. In some instances, the effects became amplified (aka faster greening out times). A test subject who smoked a joint and had a couple of shots had twice as much THC in their system.

Ultimately, the combined research found that cannabis activates your natural cannabinoid receptors, which affects how quickly your body absorbs alcohol.

Lukas attributes this to the small intestine. Marijuana alters the movement throughout your gastrointestinal tract, causing blood alcohol levels to be lower than consuming alcohol solo.

The research also found that drinking alcohol first, instead of smoking first, may increase the absorption of THC and cause “positive subjective mood effects.” This is due to alcohol’s effect on your blood vessels—opening them up and enabling THC to be absorbed at a faster rate.

A Closer Look

A 2015 study by the American Association for Clinical Chemistry confirms this. They found that the “simultaneous use (of cannabis and alcohol) produces significantly higher blood concentrations of cannabis’ main psychoactive constituent, THC,… than cannabis use alone.”

Those two joints may be intensified after a glass of alcohol.

There’s even more to consider before mixing the two. A few studies show that marijuana has an antiemetic effect, which makes it more difficult for you to vomit. But if you’ve ever had a heavy tequila night, you know that the body rids itself of excess alcohol by vomiting. Therefore, mixing the two may prevent the disposal of toxins. On top of that, it can also cause paranoia since both are depressants and slow down the central nervous system.

It’s okay if you prefer one substance over the other. Both marijuana and alcohol certainly provide their own unique effects and do different things to different users. It may just depend on what you’re looking for in the situation or moment you’re in.

Just remember that THC is absorbed into your blood faster when alcohol is involved, meaning the effects can be unpredictable. Plus, dabbing, vaping or eating cannabis could easily have different effects, as could different kinds and amounts of alcohol. When it comes down to it, just be smart about your consumption habits and learn what works best for you whether you combine the two or not. Greening out, like blacking out, is generally something that can be avoided with responsible consumption habits.

Do you like to combine cannabis and alcohol? What has been your experience?

Photo Credit: Samantha Cohen (license)


Morgan Smith Morgan Smith

A born and raised Hoosier and Indiana University alumna, Morgan Smith is a freelance writer and editor based in the Denver area. Morgan has worked with B2B, nonprofit and regional publications, but especially enjoys learning and educating others about the inner-workings of the cannabis industry. Her freelance writing supported her recent six-month solo backpacking trip to South America where she climbed volcanoes, played with llamas and jumped off a bridge.

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