Read this before you try hotboxing cannabis

Scientifically reviewed by Lauren Vrabel, PharmD

Hotboxing in a car is an intense way to get high and is not recommended for beginners (Shutterstock)

Whether you’ve participated or not, you’ve likely heard the term “hotboxing” before. The practice of filling a small enclosed area with smoke was popularized by Cheech and Chong and has become something of a ritual for cannabis enthusiasts.

What is hotboxing?

Hotboxing is the practice of smoking cannabis in an unventilated area.

Using a car is the classic way to hotbox, but you can also hotbox in the following spaces:

tent
closet
shed
attic
basement
any other room that can be sealed from airflow

Hotboxing is an intense way to get high and is not recommended for beginners. The common belief is that hotboxing will increase the effects of the THC and lead to a more intense high thanks to the lack of ventilation.

Will hotboxing get you high?

Yes, hotboxing cannabis will get you high.

Whether or not hotboxing will get you higher than simply smoking is still out for debate among scientists. Anecdotal evidence claims hotboxing provides a “double dose” of THC from the inhalation of the joint (or blunt or bong) and the residual THC in the smoke in the air, but is this enough to get you higher?

The crucial component of hotboxing is the lack of airflow. You will feel higher than normal after a hotboxing session, but that’s at least partially thanks to carbon monoxide (CO) and carbon dioxide (CO2), not just THC.

When fresh air can’t circulate, the amount of oxygen in the air drops and the amount of smoke particles increases. These increased levels of byproducts lead to an accumulation of CO and CO2 in your body, which can lead to a feeling similar to that of being high, but with lightheadedness, confusion, and drowsiness. Add this feeling with the psycho-activity of THC, and it’s easy to see why you might think that hotboxing gets you higher. ¹

Does hotboxing work without smoking?

The effects of hotboxing weed don’t stop with the people hitting the joint. Thanks to the increased potency of THC in recent years, you don’t have to smoke to get high from hotboxing.

In a room with normal airflow, being around people smoking weed won’t affect nonsmokers. But a hotbox creates an environment where the composition of the air is changed by the smoke and the exhalation. Due to the lack of oxygen and the retention of the smoke in a hotbox, even nonsmokers can get high.

A 2015 study put 12 nonsmokers in a room with six smokers. The smokers were each given ten joints and told to smoke to their heart’s content. At the end of the study, the nonsmokers were tested for THC. ²

In one session, the air was allowed to circulate normally through the room and the nonsmokers didn’t test positive for weed in their system. But in the next session, the room was sealed to create a hotbox. After that session, each of the nonsmokers felt high and had detectable levels of THC in blood and urine tests.

That’s right, just being in a hotbox caused even the nonsmokers to get high enough to fail a drug test. While breathing in secondhand smoke isn’t typically enough to get you high, that changes when you’re in a poorly ventilated room.

When should you hotbox?

It’s important to use good judgment when it comes to hotboxing because there is a right and a wrong time to light up. Here are some things to consider before you do it:

Hotboxing isn’t discreet. Hotboxing leaves a pungent aroma of cannabis, so anyone standing outside the room or car will instantly know what you’re doing. While a hotboxed car can easily air out with the windows rolled down, hotboxing someplace like a closet will leave the smell lingering for weeks.
Hotboxing is a group activity that requires a bit of planning. It takes a lot of weed to create enough smoke for a hotbox, and one joint won’t get the job done. If you’re interested in hotboxing, you’ll need a few friends (preferably with their own weed) to roll several joints, blunts, or pack a few bowls.
Don’t hotbox if you have anything else to do in a day. Plan your schedule accordingly since you’ll be hitting multiple joints at once.

Is hotboxing dangerous?

Hotboxing is not necessarily more dangerous than smoking, but you need to take a few precautions.

Never hotbox a moving car. The smoke can reduce visibility and impair the driver- even if they aren’t taking hits. This can lead to dangerous driving conditions and even cause an accident.
Ensure you’re in a safe location. If you’re hotboxing a car, don’t park in a public place filled with kids. If you’re hotboxing a room, ensure the lingering smell won’t present a problem. And it should go without saying, but never hotbox in a room or car that isn’t yours without the owner’s express permission (or participation).

Is hotboxing bad for you?

Since airflow is restricted while hotboxing, there is substantial and extended exposure to the chemicals in cannabis smoke, which could cause oxygen levels to drop and CO2 to levels rise – but this won’t typically present a problem for a seasoned smoker. ³

In rare cases, high levels of smoke can cause changes in blood oxygen levels, thanks to a build-up of carbon monoxide and carbon dioxide in the blood. Low oxygen (hypoxia) can lead to long-term health issues like altered brain function and lung disease. Still, it takes long periods of exposure to smoke to get hypoxic, and there are no significant studies to show cannabis greatly affects oxygen levels in the blood.

But still, hotboxing itself has never been studied, so make sure to get some fresh air if you’re feeling light headed, and keep in mind that people with existing heart or lung problems are the most susceptible to issues. ⁴ ⁵

Can hotboxing a car get you in legal trouble?

Hotboxing is a legal grey area. While most states don’t have specific laws forbidding hotboxing, you can find yourself facing a variety of charges depending on where you live.

You can face DUI charges for hotboxing if you’re the one in the driver’s seat. The car doesn’t need to be on, and you don’t need to be going anywhere- simply sitting in the driver’s seat under the influence can be enough to face a DUI charge in most states. In states where cannabis isn’t legal, you could face additional charges of drug and paraphernalia possession.

Certain states have rules surrounding where you can and cannot smoke cannabis. For example, in New York and California, you cannot smoke in a car. So even if you hotbox your own vehicle, you could still get in trouble if the cops show up.

Hotboxing a room is another story. In your own house, you’re not likely to face charges (unless you live in a state without legal cannabis and have really nosy neighbors.) But you can still face charges or fines if you hotbox on property that isn’t yours, including Airbnbs and rentals.

Bottom line

Hotboxing is a time-honored tradition for many cannabis enthusiasts and a good bit of fun. With some planning and discretion, you and your friends can have a high flying time and a memorable experience. But be aware that even those who don’t smoke can get high from hotboxing, and local laws and regulations can affect where you’re able to hotbox.

Sources

Wu TC, Tashkin DP, Djahed B, Rose JE. Pulmonary hazards of smoking marijuana as compared with tobacco. N Engl J Med. 1988;318(6):347-351.
Herrmann, E. S., Cone, E. J., Mitchell, J. M., Bigelow, G. E., LoDico, C., Flegel, R., & Vandrey, R. (2015). Non-smoker exposure to secondhand cannabis smoke II: Effect of room ventilation on the physiological, subjective, and behavioral/cognitive effects. Drug and alcohol dependence, 151, 194–202. https://doi.org/10.1016/j.drugalcdep.2015.03.019
Wu HD, Wright RS, Sassoon CS, Tashkin DP. Effects of smoked marijuana of varying potency on ventilatory drive and metabolic rate. Am Rev Respir Dis. 1992;146(3):716-721. doi:10.1164/ajrccm/146.3.716
Ibid
Chapman, Kyle, and Kristen E. Dragan. “Hypercarbia.” StatPearls [Internet]., U.S. National Library of Medicine, 27 July 2021, https://www.ncbi.nlm.nih.gov/books/NBK559154/.