Medical Marijuana
General Overview
Access to Cannabis for Medical Purposes Regulations (ACMPR) can access fresh or dried marijuana or cannabis oil
Requires healthcare practictioners to indicate the quantity (grams) of dried marijuana that they authorize for the patient and period of use
The licensed producer will then provide that quantity of fresh or dried marijuana or cannabis oil that is equivalent
Each provincial College has suggested guidelines and policies
Quebec CMQ physicians should not provide patients with a medical document to access medical marijuana unless part of a research project.
Sign a declaration rather than write a prescription
State that the patient meets Health Canada criteria allowing access to marijuana
Physicians cannot prescribe a drug without safeguards in place (evidence on effectiveness, safety, indications, dosing and precautions)
Factors to Consider
Evidence supporting analgesic effect of cannabis is weak
Trials of short duration, small sample sizes, incomplete outcome measures
Higher evidence for harm than for benefit
Adverse events include: CNS effects/confusion/sedation/"high"/dysphoria, speech disorders, dizziness, ataxia, numbness, impaired concentration or memory, hypotension, psychiatric, hallucination, psychosis
Smoked cannabis was compared against placebo (not other cannabis formulations or standard analgesics)
Smoke is a hazardous delivery system
Smoke contains chemicals potentially carcinogenic or harmful to heart or other organs
Cannabis can already be prescribed as
Oral capsule (Nabilone) - indicated for chemotherapy induced N/V
Inhaled spray (Sativex) - spasticity or neuropathic pain from MS or cancer
CFPC Recommendations
Some evidence are for refractory (third/fourth-line) chemotherapy induced N/V, spasticity due to MS or spinal cord injury, neuropathic or palliative cancer pain
No evidence for pain conditions such as fibromyalgia or low back pain
May only consider in neuropathic pain if failed to respond to standard treatments (adequate trial of pharmacologic, nonpharmacologic, and pharmaceutic cannabinoids)
Dried cannabis is NOT appropriate for
Anxiety/insomnia
Age <25yo
Personal or strong family history of psychosis
Active substance use disorder
Cardiovascular disease (angina, peripheral vascular disease, cerebrovascular disease, arrhythmias)
Respiratory disease
Pregnant, planning pregnancy, breastfeeding
Caution in patients with
Concurrent active mood/anxiety disorder
Smoke tobacco
Risk factors for cardiovascular disease
Heavy use of alcohol, opioids, benzodiazepines, or other sedative medications
Prior to signing a medical document authorizing dried cannabis for pain
Conduct a pain assessment
Assess for anxiety/mood disorders
Assess for substance use disorder
Inform of harm reduction strategies
Regularly monitor
Function, quality of life, pain relief
Misuse, abuse
Discontinue therapy if not effective or causing harm
Not be allowed to drive for at least 4 hours after inhalation, 6 hours after oral ingestion, 8 hours if experiences euphoria
References:
CMPA 2014 (revised 2016). https://www.cmpa-acpm.ca/en/advice-publications/browse-articles/2014/medical-marijuana-new-regulations-new-college-guidance-for-canadian-doctors
BC 2015 (revised 2016). https://www.cpsbc.ca/files/pdf/PSG-Cannabis-for-Medical-Purposes.pdf
CFPC