Medical Cannabis

Cannabis has properties that may be useful for pain and symptom management for people living with chronic diseases, and it has been legal in Canada since 2001. This guide will help you understand medical cannabis and make an informed choice about using it – while helping protect your lungs along the way.

Is Medical Cannabis Right For Me?

As with any therapeutic agent, your healthcare provider can help you understand the potential benefits and risks of medical cannabis treatment. Your healthcare provider will consider things like your illness(es), symptoms, and any other medications you take. Additionally, you should tell your doctor if you have any personal or family history of psychosis.

Medical cannabis may be prescribed for managing symptoms for a variety of health concerns, including:

  • Chronic pain
  • Arthritis and back pain
  • Irritable Bowel Syndrome (IBS)
  • Insomnia and sleep disorders
  • Anxiety
  • Depression
  • Post-traumatic Stress Disorder (PTSD)
  • Cancer pain
  • Neuropathic pain
  • Palliative pain
  • Migraines and headaches
  • Nausea or vomiting (including with chemotherapy)
  • Multiple sclerosis pain or spasticity
  • Seizure disorders and epilepsy
  • Appetite stimulation
  • Alcoholism
  • Opioid and/or benzodiazepine dependence or addiction
  • Stress Disorders

Medical cannabis is not recommended for people who are pregnant or breastfeeding.

How does medical cannabis work?

The cannabis plant contains more than 100 different chemical compounds called cannabinoids, all with different effects on the body.

The two that you’ll hear mentioned the most are Tetrahydrocannabinol (THC) and Cannabidiol (CBD):

  • THC is psychoactive – it binds with certain receptors in the brain and produces a “high” feeling. However, THC has important therapeutic benefits related to pain relief, helping with sleep, and appetite stimulation.
  • CBD is not psychoactive – it does not produce the “high” associated with THC. It is being investigated for multiple benefits, including pain management and anti-inflammatory properties. It is thought that CBD may block some of the psychoactive effects of THC.

Different strains of cannabis will have different levels of the various cannabinoids. Patients who are new to medical cannabis should aim to start with CBD-dominant strains that have low amounts of THC at 1% or less. 

Will I have to smoke it?

Definitely not! Medical cannabis is available in many forms. The Lung Health Foundation does not recommend the smoking of any substances.

Instead of smoking, consider using cannabis products that are in oil, gel cap, or tablet forms. The dried flower can also be used with an inhalation device called a vaporizer, though this does still carry some risk to the lungs.

Your healthcare provider will help you select the best form of cannabis for you.

How will I know how much to use?

 Your healthcare provider will consider a number of factors when determining your dose and method of consumption. Considerations may include whether you need relief from acute (rapid onset) or sustained (longer term) symptoms.

As per Health Canada, the average authorized amount of dried cannabis for medical purposes is two grams per day, for 180 or 365 days.

What are the most common side effects?

All medicines and treatments have the potential for side effects, and medical cannabis is no exception. The most common side effects of medical cannabis are:

  • Dry mouth
  • Racing heart
  • Drowsiness
  • Dizziness
  • Eye redness
  • Inability to think clearly or concentrate

Consult your healthcare provider at any time if you are concerned.

I have a prescription from my doctor. How do I access medical cannabis? 

Medical cannabis should only be purchased from legal channels and sources.

According to Health Canada, if you are authorized by your healthcare provider, you can access cannabis for medical purposes by:

  • Placing an order through an authorized online sales platform.
  • Registering with Health Canada directly to grow a limited amount of cannabis for your own personal use, or designating someone to grow and produce it for you;
  • Shopping in person at provincial or territorial authorized retail outlets; or
  • Buying directly from a federally licensed seller.

The conditions needed to successfully grow your own cannabis could carry risks to the air quality of your home, including increased exposure to airborne mould.

Will my insurance cover medical cannabis?

Many insurance providers have started to offer group benefit plans that cover medical cannabis. Coverage may be available for the following conditions:

  1. Cancer with severe pain
  2. Chemotherapy-induced nausea vomiting
  3. Multiple Sclerosis with neuropathic pain
  4. Multiple Sclerosis with spasticity
  5. Rheumatoid Arthritis with pain
  6. HIV/AIDS with anorexia
  7. HIV/AIDs with neuropathic pain
  8. Palliative care

Some insurance providers that do not list medical cannabis as a specific treatment option may cover medical cannabis under a Healthcare Spending Account (HSA). Check with your insurance provider for exact details on possible coverage.

Safety guidelines

There are some additional guidelines you should follow if you are using medical cannabis:

  • Do not smoke cannabis, either medically or recreationally.
  • Do not operate a motor vehicle, use heavy machinery, or engage in high-risk activities after using medical cannabis. Depending on the person and products used, the effects may last at least six hours.
  • Never combine medical cannabis and alcohol.
  • Do not use medical cannabis if you are pregnant or breastfeeding.
  • As with any drug or treatment, take precautions to keep your medical cannabis away from young persons.

Questions about medical cannabis?

For general questions about cannabis and your lung health, our Certified Respiratory Educators are standing by. Access our free Lung Health Line by phone 1-888-344-LUNG (5864) or through our livechat.

To learn more about available medical cannabis products offered by Health Canada’s authorized licensed producers, or to make a purchase with a valid prescription, visit