What is cannabis?
Cannabis is a plant and drug that is thought to pre-date humans. Fossilised pollen indicates that cannabis evolved around 20-25 million years ago after diverging from its closest plant relative Humulus (or hops) around 27.8 million years ago.
Is cannabis addictive?
According to the NHS, 10% of regular cannabis users become dependent upon the substance. This risk of dependency is believed to be higher if you begin cannabis use in your teenage years or use cannabis every day.
Like other drugs, you can also develop a tolerance to cannabis, meaning that higher quantities of the substance may be eventually required by users to garner the same effects they originally felt when they were cannabis naïve.
How does cannabis consumption affect the body?
The consumption of cannabis affects the body’s endocannabinoid system. Put very simply, the endocannabinoid system acts like a modulator of the release of other neurotransmitters in the body.
The endocannabinoid system seems to have very far-reaching effects. This is unsurprising given the substantial distribution of cannabinoid receptors throughout the body. The endocannabinoid system is thought to influence bodily functions such as: memory, pain modulation, sleep, appetite, the stress-response and the action of the reproductive systems.
What’s the difference between medical cannabis and recreational cannabis?
Medical cannabis is the term for plant derived cannabis products that are prescribed specifically by medical practitioners.
Recreational cannabis is defined as any cannabis used for non-medical purposes. Throughout Europe, recreational cannabis is mostly illegal. For more information on legislation in different countries across Europe look at our foundation course module on law and regulations.
The Academy of Medical Cannabis does not endorse the use of recreational cannabis and only supports the use of medical cannabis prescribed by medical practitioners.
How long has medical cannabis been used for?
Experts are fairly sure that cannabis was one of man’s first forms of medicine, with ancient Chinese texts suggesting it was first used as a food or for its psychoactive properties around 6000 years ago.
- · In Japan, cannabis was cultivated from the pre-Neolithic period onwards for its fibres but also as a food source.
- · In India, cannabis has been used for thousands of years, particularly in the spring festival of Holi.
- · Cannabis was also used in ancient Egypt as an anti-anxiety drug and as a remedy for pain, epilepsy and eye conditions.
- · Ancient Romans and Greeks used it as a surgical pain reliever and in food and wine. Cannabis was also used as a muscle relaxant and to treat tumours, childbirth complications and headaches.
- · The ancient Assyrians were aware of cannabis’ psychoactive properties and often used it in religious ceremonies. The Assyrians likely discovered cannabis’ psychoactive properties through the Aryans.
- · Hebrews are thought to have used cannabis as a medicine and in ritual ceremonies.
What is CBD?
The most common cannabinoid in the cannabis plant is CBD (Cannabidiol). CBD is also the most prevalent non-psychoactive cannabinoid.
CBD works by binding to the endocannabinoid system, with its mode of action being largely through activating other neurotransmitter systems in the body. In terms of effects, CBD is most well-known for its anti-anxiety and anticonvulsant qualities. For instance, CBD is the only constituent of GW Pharma’s Epidiolex – a 99.9 percent pure CBD product made to treat childhood-resistant epilepsy.
Aside from these popularised anti-anxiety effects, CBD is also believed to have:
- · Some anti-cancer effects (in vitro and in vivo preclinical studies only)
- · Anodyne properties
- · Neuroprotective qualities
One of CBD’s most useful characteristics is that it is thought to counteract the psychoactive effects often associated with THC – it is now largely understood that a relatively small amount of THC can be cancelled out with a comparatively large amount of CBD.
What is THC?
THC, or tetrahydrocannabinol, is one of the most prevalent psychoactive cannabinoids in cannabis. It’s believed to constitute around 12 and 20 percent of the dried content in some cannabis strains and up to 25 to 30 percent in more potent forms of the plant.
THC is most recognised as the compound that creates the high typically associated with recreational cannabis use.
THC is known to have multiple medicinal properties and uses. Specifically, we know it:
- · Has pain-killing properties
- · Is anti-inflammatory
- · Is a muscle relaxant
- · Exhibits anti-nausea effects
- · Is anti-oxidant
What is CBD oil?
CBD oil is a substance made from extracted CBD from the cannabis plant, which is then diluted using what is known as a ‘carrier oil’ such as hemp seed or coconut oil.
GPs should be aware that discussions with patients about commercial CBD products should only be in regard to more minor lifestyle and dietary benefits and should only be discussed at the same time as assessments about proper clinical therapy are also taking place.
How can I consume medical cannabis?
Medical cannabis products can come in many forms, for example as tinctures, oils, edibles or capsules.
However, not all methods of ingestion are recommended medically. Each method of ingestion has its own pros and cons so weighing up the overall benefit in each case is essential.
For more information on ingestion methods take a look at our dosing and prescribing module.
What are the benefits of medical cannabis use?
Medical cannabis is primarily identified as an effective tool for the management of a number of symptom profiles for a range of otherwise hard-to-treat conditions.
To date, conditions for which medical cannabis is supported for use in effective treatment includes:
- Treatment-resistance epilepsy
- Chemotherapy-induced nausea and vomiting
- Chronic pain
- Treatment of movement disorder symptoms ie MS pain and spasticity
- Appetite stimulation for conditions like anorexia and cachexia
There are also numerous avenues of exploration into other areas that currently require more research before being widely adopted in clinical practice:
- Gastrointestinal conditions ie Crohn’s disease
- Management of mental health disorders ie PTSD
- Management of palliative care scenarios ie cancer care symptom management
For more information on cannabis’ medical uses we suggest viewing our free foundation modules which discuss the use of medicinal cannabis for a range of neurological indications and the range of possible medicinal cannabis applications towards mental health issues.
What are the health risks of medical cannabis?
Although there may be health risks associated with recreational cannabis due to a higher THC content, which is more likely to induce psychoactive effects, medical cannabis use is monitored by medical professionals who are the only people who are legally allowed to prescribe such medicines.
With this in mind, any negative side effects of cannabis-based medications can be monitored by the prescribing professional and the treatment can be appropriately altered to better suit the patient in question.
For more information on specific side effects of different medical cannabis products please see our medical cannabis essentials module where side effects, contraindications and drug interactions are discussed at length.
Who can use medical cannabis?
Anyone who can get a prescription from a medical professional in a country where medical cannabis is legal can access medical cannabis. Conditions that might merit a prescription from a doctor include: epilepsy, multiple sclerosis, Parkinson’s, anxiety, depression and fibromyalgia amongst other conditions. The type of prescription offered is dependent upon a consultation with a medical professional regarding the personal needs of the patient and contra-indications with other medicines they may be taking.
Can you overdose on medical cannabis?
Technically no; while there have been some suspected cases of cannabis overdose, medical specialists are unclear on whether these cases were as a result of pre-existing conditions or other contributing factors.
What are the effects of taking medical cannabis with tobacco, alcohol or other pharmaceutical drugs?
As cannabinoids, including CBD and THC, share breakdown enzymes with a number of other health supplements and pharmaceutical drugs, it is a possibility that treatment that occurs at the same time as use of another drug or herb may have an effect on the metabolism and absorption of the cannabis-based medicine.
For more scientifically backed information about medical cannabis take a look at our evidence base, a ground-breaking systematic review of the history of research in this area and a global first-of-its-kind searchable database for clinical referencing.
The rest of our comprehensive resources on medical cannabis are available on our website. We urge anyone considering the use of medical cannabis products to consult with a trained medical professional prior to beginning use.