“Simplified Guideline for Prescribing Medical Cannabinoids in Primary Care”, published in Canadian Family Physician, stated that there is limited evidencesupporting the reputed benefits of medical marijuana for many conditions, and said what benefits do exist may be balanced out or even outweighed by the harms.
“While enthusiasm for medical marijuana is very strong among some people, good-quality research has not caught up,” said Mike Allan, director of evidence-based medicine at the University of Alberta and project lead for the guideline.
The guideline, created after an in-depth review of clinical trials involving medical cannabis to be distributed to 30,000 Canadian clinicians, and overseen by a committee of doctors, pharmacists, nurse practitioners, nurses and patients, examined cannabinoids for the treatment and side effects of pain, spasticity, nausea and vomiting.
For nerve pain, 30 per cent of patients given a placebo saw a moderate improvement in their pain while 39 per cent experienced the same effect while on medical cannabinoids. In patients with muscle spasticity, 25 per cent of those taking a placebo saw a moderate improvement compared to 35 per cent on medical cannabis. The use of medical cannabis was best supported in its use for chemotherapy patients experiencing nausea and vomiting. Just under half of patients using cannabinoids for their symptoms had an absence of nausea and vomiting compared to 13 per cent on placebo.
While the researchers found evidence supporting the use of medical cannabinoids to be limited, side-effects were both common and consistent.