Cannabis Made Clear

Consuming Cannabis: Inhalation

Cannabis can be consumed in many ways, each with its own pros and cons. Discover how inhaling cannabis can affect your mind and body.

Inhalation is a common way to consume cannabis, but there are many factors to consider before you do. Read on to learn how inhalation influences the way your body absorbs cannabinoids, how quickly effects may occur and how you can minimize potential risks.

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Inhalation involves inhaling heated cannabis vapour or smoke through your mouth and into your lungs. When you inhale, the cannabinoids travel into your lungs, where they are absorbed into your bloodstream. You can inhale cannabis through a pre-roll or rolled joint, bong, dried flower vaporizer, vape pen (which uses a cartridge containing a liquid cannabis extract, rather than dried cannabis) and other devices, such as a dab rig or pipe.


In terms of dosing, it’s always best to start low and go slow. Begin with a single inhalation and then wait 10 to 15 minutes to determine the effects before inhaling more. Consider recording your reactions and monitoring them to fully understand how much cannabis to use to achieve the desired effect. You might also opt for a strain with low THC (less than 12% total THC content).


When cannabis is inhaled, the effects can be felt quickly — within seconds or minutes — as the cannabinoids are absorbed through the lungs directly into the bloodstream. Effects generally peak after about 30 minutes and last up to six hours. Keep in mind that different products will affect everyone differently (based on factors such as age, sex, overall health and previous experience with cannabis), and these are only guidelines.

Reducing risk

Inhaling cannabis is not without its risks. There is substantial evidence that shows that the smoke produced by combusted cannabis contains many of the same cancer-causing chemicals as tobacco smoke. There is also substantial evidence that daily cannabis smoking leads to pre-cancerous lesions in the airway. Exposure to second-hand smoke is harmful, but you can reduce the risk by consuming cannabis away from others.

Different methods of inhalation have different levels of risk. For example, smoking a rolled joint or pre-roll poses a greater risk than using a dried flower vaporizer or vape pen (these devices typically heat cannabis to just below the point of combustion, creating vapour rather than smoke). That doesn’t mean all other inhalation methods are risk-free. For example, there’s a common myth that water bongs are safer than joints because the smoke passes through water before reaching your mouth, cooling it; it’s thought that the water also helps filter out harmful compounds. While it’s true that the smoke is cooled, there’s evidence to suggest that water bongs may actually increase your intake of tar and ash particles.

It’s also a myth that longer or deeper inhalation can lead to stronger effects. In actuality, the THC takes just seconds to absorb into your system, so holding your breath won’t make a difference. To minimize risk, take shallow puffs rather than deep inhalations, do not hold in cannabis smoke and don’t mix tobacco into your stash.

Avoid combining cannabis with other substances, such as alcohol and tobacco. Doing so could lead to unwanted effects, and mixing alcohol and cannabis can compound the risk of impairment. Once again, start low and go slow for best results.

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Canadian Centre on Substance Use and Addiction
Evidence statements, Monitoring Health Concerns Related to Marijuana
Colorado Department of Public Health and Environment
Cannabis in Canada: Get the Facts
Health Canada
Lower-Risk Cannabis Use Guidelines: A Comprehensive Update of Evidence and Recommendations
American Journal of Public Health
Lower-Risk Cannabis Use Guidelines (LRCUG) for Youth
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