Knowing how long cannabis stays in your system is important, especially if you’re working, travelling, or considering your ability to drive. For medical cannabis patients, understanding this can also help you feel more confident about your treatment and its potential impact on daily life.
When starting medical cannabis, it’s common to begin with a low dose and gradually increase over time to minimise the risk of side effects. Most patients find that they can continue with work or driving without issue, but it’s important to approach new medications cautiously.
If you feel drowsy, dizzy, or struggle to focus, it’s best not to drive, operate machinery, or sign important documents. These effects can happen with any medication, and medical cannabis is no different. Waiting to see how it affects you, particularly when starting or adjusting your dose, is a good way to stay safe.
Lots of factors affect how long medical cannabis stays in your system, including metabolism, frequency of use, and body composition. To make things clearer, let’s break down how cannabis works in the body and how it’s detected.
What is the Half-Life of Cannabis?
The “half-life” of a medicine is the standard measure that doctors use to understand how long it takes to process and remove it from your body. A medicine’s half-life isn’t always exact, because things like your age and health can change how long it stays in your system. But it’s a helpful guide for doctors to choose the right medicine and dose for you.
Cannabis contains cannabinoids, like THC and CBD, which interact with your body in different ways. These are processed by your liver and broken down into smaller substances called metabolites. These metabolites stick around longer and are what most tests detect.
For a deeper dive into cannabinoids, check out our blog CBD vs. THC: What’s the Difference?
How Cannabis is Detected
Cannabis tests are often looking for THC, the psychoactive compound known for creating the sensation of a “high.” However, new tests are starting to look at a wider range of cannabinoids as we learn more about their health benefits.
The way cannabis is consumed can also affect how it behaves in your body. For example, when cannabis is inhaled THC and CBD enter the bloodstream quickly and reach their highest levels within minutes. On the other hand, ingested cannabis takes longer to absorb – especially if taken with food – but its effects may last longer 1 2 .
Cannabinoids also dissolve easily in fat, which means factors like body fat, metabolism, and dose can all influence how long they are detectable in the body.
Factors That Affect How Long Cannabis Stays in Your System
These factors can make a big difference in how quickly your body processes cannabis:
- How Much You Use: Regular or higher doses can build up in the body, making them detectable for longer. Occasional use or smaller doses usually clear more quickly.
- Metabolism: People with faster metabolisms may break down and eliminate cannabinoids from their systems more quickly.
- Body Fat: THC and CBD bind to fat cells, so they might linger longer in people with higher body fat.
- Age and Health: Younger or more active people tend to metabolise cannabis faster.
- How You Take It: How cannabis is consumed – through inhalation or ingestion – influences how quickly it enters and leaves the bloodstream.
Conclusion
Understanding how cannabis interacts with your body is key to feeling confident about using medical cannabis safely. While tests can detect cannabinoids for days or even weeks, the effects don’t last nearly as long, especially at medical doses.
At Curaleaf Clinic, we’re here to support you through every step of your medical cannabis journey. If you’re concerned about driving, work, or testing, speak with your healthcare provider for advice tailored to you. With the right guidance, you can safely benefit from medical cannabis while continuing with your day-to-day life.
Glossary
Cannabidiol (CBD): A cannabinoid found in cannabis. It interacts with the body’s endocannabinoid system and other signalling systems, such as dopamine and serotonin. CBD can be prescribed for chronic pain, anxiety, and epilepsy when first-line treatments have failed.
Cannabinoid: A chemical compound found in cannabis plants, produced naturally by the body, or created synthetically. Cannabinoids interact with the endocannabinoid system, which regulates functions like mood, pain, and immunity.
Half-Life: The “half-life” of a medicine is the standard measure that doctors use to understand how long it takes to process and remove it from the body.
Medical Cannabis: Medical cannabis refers to the use of the cannabis plant or its compounds for therapeutic purposes. It is prescribed by healthcare professionals to help manage symptoms of various medical conditions.
Metabolite: Cannabis contains cannabinoids which are processed by the liver and broken down into smaller substances called metabolites. These metabolites are what most cannabis tests detect.
Tetrahydrocannabinol (THC): A cannabinoid found in cannabis. In medical settings, it can be prescribed for conditions like chronic pain, nausea, and spasticity when other treatments are ineffective.
Sources
1 Chayasirisobhon, S. (2020). Mechanisms of Action and Pharmacokinetics of Cannabis. The Permanente Journal, 24(5). doi:https://doi.org/10.7812/tpp/19.200. Available at: https://www.thepermanentejournal.org/doi/pdf/10.7812/TPP/19.200
2 Lucas, C.J., Galettis, P. and Schneider, J. (2018). The pharmacokinetics and the pharmacodynamics of cannabinoids. British Journal of Clinical Pharmacology, [online] 84(11), pp.2477–2482. doi:https://doi.org/10.1111/bcp.13710. Available at: https://bpspubs.onlinelibrary.wiley.com/doi/full/10.1111/bcp.13710
