A healthcare provider, in collaboration with a patient, determines the most suitable strain, dosage and appropriate consumption method of medical cannabis.
You may need to try multiple strains to identify the strains that work best for you and your symptoms.
Cannabis is generally prescribed as a maximum daily allowed quantity. You may use your medical cannabis only once daily or at multiple times during the day. You may consume your cannabis through different consumption methods and may use the same or different strains.
Two methods of administration are generally recommended: oral administration or administration through inhalation. Each has different onsets, effects and duration.
Oral Administration
Consuming medical cannabis is one option for some patients. THC can be absorbed orally through ingestion of foods containing cannabis (e.g. butters, oils, brownies, cookies), and teas prepared from leaves and flowering tops. While oral administration results in a slower onset of action there is a longer duration of effects compared to smoking or vaporization.
When medical cannabis is consumed as tea, it takes at least 30 to 90 minutes before any effects occur. The maximum effect is usually achieved after 2 or 3 hours, and it takes 4 to 8 hours to wear off. Eating high-fat food together with the tea can improve the absorption of the active substances [1].
Inhalation Administration
Inhaling the vapours released by heating the medicinal cannabis is one form of administration. When inhaled, the medicinal cannabis is absorbed into the bloodstream via the lungs. Inhaling cannabis produces a stronger and faster therapeutic effect than orally consuming the product. When inhaled, the active ingredients of cannabis are absorbed quickly into the body. The maximum effect occurs within 15 minutes of inhalation, and slowly wears off over a 3 to 4 hour period.
Vaporization
Vaporizers are used to inhale medical cannabis. Inhalation by vaporization is a lower-temperature process that provides a more efficient extraction of THC and CBD than other administrations. Studies have shown that vaporizing medical cannabis exposes the user to lower levels of harmful toxic by-products such as carbon monoxide, polycyclic aromatic hydrocarbons (PAHs), and tar than through smoking.
Smoking
Smoking cannabis on a regular basis can damage the lungs and can lead to infections in the nose, throat and lungs. For this reason, smoking medicinal cannabis is not recommended.
Inhalation of medicinal cannabis using a vaporizer is a more suitable method.
Cannabis Vaporization: http://www.ccic.net/index.php?id=132,742,0,0,1,0
Dosage and use
While there is no science-based data to determine the appropriate dosage for medical cannabis use for specific medical conditions, published patient information is available from The Office of Medicinal Cannabis, which provides helpful guidelines [2] for both oral and vaporization methods.
Before starting any form of treatment, please consult with your healthcare practitioner.
Start low and go slow
The rule of thumb for starting to use medical cannabis is to start low and go slow. By proceeding in a slow and gradual fashion, waiting a few minutes in between inhalations from a vaporizer, patients can gauge whether it’s the correct potency and observe for possible over dosing. An increase in dosage, if necessary, should be carried out slowly until a patient reaches a comfortable dose [1].
Patients with no prior experience with cannabis or cannabinoids are advised to begin at a very low dose and to stop immediately if undesirable side-effects occur [3].
Medical cannabis strains
Medical cannabis is available in a wide variety of strains, from both Cannabis sativa and Cannabis indica plants and in combinations of those two. Tetrahydrocannabinol (THC) and cannabidiol (CBD) are associated with the treatment and management of different conditions and illnesses. An incredibly complex interaction occurs between the two active components and the 700 other metabolites in the whole bud cannabis. One conclusion that has been drawn from research is that CBD, as a non-psychoactive component of cannabis, tempers and reduces the psychoactive effect of THC [4].
The strain best suited to treat a specific medical condition depends on the symptoms being treated. According to The Office of Medicinal Cannabis, inhaling medical cannabis with high CBD content provides effective relief for pain and muscle spasms. Therefore, the anti-inflammatory properties of CBD may be more effective for patients suffering from inflammatory conditions. On the other hand, cannabis with high levels of THC is preferred for chemotherapy symptoms such as weight loss, nausea and vomiting [5].
In the case of chronic neural pain, the Office of Medicinal Cannabis recommends a close ratio of THC to CBD.
Cancer-related conditions:
A healthcare practitioner may authorize the use of medical cannabis for the relief of one or more of the following symptoms associated with a number of cancer-related conditions, which have not responded to conventional medical treatment. These symptoms (or conditions) may include:
- Chemo-induced nausea and vomiting (CINV);
- Loss of weight and appetite in cancer patients (and patients with HIV/AIDS);
- Pain and muscle spasms;
- Chronic non-cancer pain (mainly neuropathic);
- Severe refractory cancer-associated pain;
- Insomnia and depressive moods due to chronic diseases; and
- Symptoms encountered during in an end-of-life care setting [6].
Medications containing medical cannabis available in Canada:
There are a number of prescription medications containing medical cannabis that have been authorized for sale under the Food and Drug Regulations (FDR) in Canada. These include [7]:
- Marinol®: A capsule containing synthetic THC. Originally, authorized for the treatment of AIDS-related anorexia and CINV. While still approved for use in Canad it was discontinued by the manufacturer.
- Cesamet®: A capsule containing nabilone, a synthetic cannabinoid, it is authorized for the management of CINV. More recent clinical trials report starting doses of nabilone of 0.5 mg at night to help treat pain or insomnia induced by fibromyalgia and insomnia in PTSD.
- Sativex®, or nabiximols, is a buccal spray containing extracts of cannabis and a standardized concentration of THC and CBD. Nabiximols are authorized to treat some symptoms of multiple sclerosis. In is conditionally authorized for pain relief in adults with advanced cancer. Current dosing recommendations for nabiximols suggest a maximum daily dose of 12 sprays (32.4 mg THC and 30 mg CBD) over a 24 h period
[1] “Information for Health Care Professionals Cannabis (marihuana, Marijuana) and the Cannabinoids”. Health Canada. Health Canada, Feb. 2013. Web. 10 Nov. 2014.
[2] “Medicinal Cannabis Information for Patients.” Institute for Responsible Medicine Use and the Office of Medicinal Cannabis of the CIBG, Ministry of Health, Welfare and Sport, Feb. 2011. Web. 10 Nov. 2014.
[3] “Information for Health Care Professionals Cannabis (marihuana, Marijuana) and the Cannabinoids”. Health Canada. Health Canada, Feb. 2013. Web. 10 Nov. 2014.
[4] ‘The Cannabinoid Spectrum.’ Tweed – American Herbal Pharmacopoeia’, n.d. Web. 21 Oct. 2014
[5] “Medicinal Cannabis Information for Patients.” Institute for Responsible Medicine Use and the Office of Medicinal Cannabis of the CIBG, Ministry of Health, Welfare and Sport, Feb. 2011. Web. 10 Nov. 2014.
[6] “Information for Health Care Professionals Cannabis (marihuana, Marijuana) and the Cannabinoids”. Health Canada. Health Canada, Feb. 2013. Web. 10 Nov. 2014.
[7] “Marihuana for Medical Purposes Regulations.” Canada Gazette. Government of Canada, 15 Dec. 2012. Web. 12 Nov. 2014.