What are the potential long term effects of medical cannabis use?
5 min read
Sam North
While many of the currently available clinical studies focusing on medical cannabis have shown positive results and a high safety profile, there are still lingering concerns about the potential long-term effects of its administration.
One of the main issues is that there simply hasn't been enough research conducted on the long-term effects of medical cannabis, as in most jurisdictions, it is still a relatively new treatment option. However, based on the available evidence and expert opinions, there are some potential long-term effects that all UK medical cannabis patients should definitely be aware of.
Here, we take a concise but also comprehensive look at what the science says about the potential long-term effects of medical cannabis administration.
Contents
What are the potential long-term effects of medical cannabis administration?
Apart from the obvious risk that smoking medical cannabis poses to the respiratory system (which we dive into below this section), there are some potential long-term physiological effects that could occur with any method of administration that all patients should be aware of.
Tolerance and dependence
One of the concerns with long-term use of medical cannabis is the potential development of tolerance, meaning that higher doses of the active ingredient/s may be needed to achieve the same therapeutic effects. This can also lead to a risk of dependence, but all UK medical cannabis patients are monitored by healthcare professionals, reducing this risk significantly.
Changes in brain structure and function
Some studies show that long-term cannabis use can alter brain structure and function, especially in areas linked to memory and cognition. It's unclear if these changes are permanent or reversible once use stops. Adolescents and young adults are most at risk, as their brains are still developing.
Hormonal changes
Another potential concern is the impact of long-term medical cannabis use on hormones, particularly in women. Some studies have shown that cannabis can interfere with the menstrual cycle and affect hormone levels in women. Men may also experience changes in testosterone levels and sperm quality with long-term cannabis use.
Cardiovascular effects
While studies have shown that acute cannabis use can actually improve cardiovascular health, long-term use has been linked to an increased risk of heart disease and stroke. This is thought to be due to the effects of THC on blood pressure and heart rate.
Cannabinoid Hyperemesis Syndrome
This rare condition is caused by long-term, heavy use of cannabis and can lead to extreme nausea, vomiting, and abdominal pain. It is not fully understood yet, but some experts believe it may be linked to changes in the way the body processes cannabinoids over time. Again, healthcare professionals carefully monitor UK medical cannabis patients to reduce any/all of the risks.
Does the method of administration matter?
Yes, certain ways of taking medical cannabis are 'riskier' than others and can lead to more serious health implications.
Can patients legally smoke medical cannabis in the UK?
Dried medical cannabis flower is a legal option for specialists to prescribe in the UK, but smoking medical cannabis flower is illegal. This is due to the overwhelming evidence of the negative effects of smoking on lung health.
How is dried medical cannabis flower legally administered in the UK?
Through a vaporisation device, inhaled dried medical cannabis flower is legal for specialists to prescribe in the UK. This method of administration delivers a fast onset of effects (slightly slower than if smoked, but comparable), which can be hugely beneficial for patients experiencing sudden or severe symptoms.
Vaping is a fairly new innovation, and as such, there is no long-term data on the potential effects of vaping medical cannabis. However, early studies have shown that vaporising medical cannabis can be a safer way to take medical cannabis than smoking, with fewer long-term risks.
Are there other ways to take cannabis-based medicines?
Yes, there are a range of cannabis medicine options and application methods that do not involve inhalation of smoke or vapor, cutting the risk of long-term effects to the respiratory system (and dental, mouth, and esophageal health).
Medical cannabis oils and tinctures can be taken sublingually (under the tongue), consumable products like edibles and capsules can be ingested orally, and topical creams or patches can be applied directly to the skin.
Final thoughts
It is important that all potential and current medical cannabis patients here in the UK have a full understanding of all the risks and potential long-term effects of medical cannabis use. Knowledge is power; information is key - it is essential that patients stay informed and communicate openly with their prescribing specialist/clinical team about any concerns or questions they may have.
And although there are some long-term (and short-term) side effects relating to the application of cannabis-based medicines (and most conventional pharmaceutical options), it is also important to remember that many patients are experiencing life-changing, therapeutic effects from medical cannabis.
If you would like to learn more, check out our education and blog sections.
We also provide a fast and free eligibility screening service, for those who are interested in finding out if they may be eligible for a UK medical cannabis prescription. It takes less than 30 seconds to complete, and you will receive your results immediately.
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Sam North, a seasoned writer with over five years' experience and expertise in medicinal cannabis, brings clarity to complex concepts, focusing on education and informed use.
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All of our articles are written by medical cannabis experts, guided by strict sourcing guidelines, and reference peer-reviewed studies and credible academic research. Our expert clinical team and compliance specialists provide valuable insights to ensure accuracy when required. Learn more in our editorial policy.
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