Abstract
There has been much recent discussion and debate surrounding cannabis in Canada, including the prescribing of medical cannabis for therapeutic purposes. Certain commentators–including the Canadian Medical Association (CMA)–have denounced the prescribing of cannabis for medical purposes due to a perceived lack of evidence related to the drug’s efficacy, harms, and mechanism of action. In this commentary, we present arguments in favour of prescribing medical cannabis in Canada. We believe the anti-cannabis position taken by CMA and other commentators is not entirely evidence-based. Using the example of neuropathic pain, we present and summarize the clinical evidence surrounding smoked or vapourized cannabis, including recent evidence pertaining to the effectiveness of cannabis in comparison to existing standard pharmacotherapies for neuropathy. Further, we outline how the concerns expressed regarding cannabis’ mechanism of action are inconsistent with current decision-making processes related to the prescribing of many common pharmaceuticals. Finally, we discuss potential secondary public health benefits of prescribing cannabis for pain-related disorders in Canada and North America.
Key Words: Cannabis, medical marijuana, pain, Canada
Résumé
Il y a eu récemment de nombreux débats et discussions sur le cannabis au Canada, notamment sur la prescription du cannabis médical à des fins thérapeutiques. Certains commentateurs–dont l’Association médicale canadienne (AMC)–dénoncent la prescription du cannabis à des fins médicales en raison du manque perçu de preuves de l’efficacité potentielle, des méfaits et du mécanisme d’action de cette drogue. Nous présentons ici les arguments en faveur de la prescription du cannabis médical au Canada. Nous croyons que la position anti-cannabis adoptée par l’AMC et par d’autres commentateurs n’est pas entièrement fondée sur les données probantes. En prenant l’exemple de la douleur neuropathique, nous présentons et nous résumons les preuves cliniques portant sur le cannabis fumé ou vaporisé, y compris les preuves récentes afférentes à l’efficacité du cannabis comparativement aux pharmacothérapies standard existantes contre les neuropathies. De plus, nous montrons que les préoccupations exprimées au sujet du mécanisme d’action du cannabis sont en contradiction avec les processus décisionnels actuels liés à la prescription de nombreux produits pharmaceutiques courants. Enfin, nous discutons des éventuels avantages secondaires pour la santé publique du fait de prescrire le cannabis pour les troubles liés à la douleur au Canada et en Amérique du Nord.
Mots Clés: cannabis, marijuana médicale, douleur, Canada
Footnotes
Conflict of Interest: Dr. Montaner has received financial support from the US National Institutes of Health, International AIDS Society, United Nations AIDS Program, World Health Organization, France Recherche Nord & Sud SIDA HIV Hépatites (ANRS), International Association of Providers of AIDS Care (IAPAC), UNICEF, MAC AIDS Fund and Open Society Foundation. He has received grants from Abbvie, Boehringer Ingelheim, Bristol-Myers Squibb, Gilead Sciences, Janssen, Merck and ViiV Healthcare.
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