Cannabis as an Adjunct to or Substitute for Opiates in the Treatment of Chronic Pain

Philippe Lucas
Journal of Psychoactive Drugs, 44:2, 125-133
June 2012

publicationThere is a growing body of evidence to support the use of medical cannabis as an adjunct to or substitute for prescription opiates in the treatment of chronic pain. When used in conjunction with opiates, cannabinoids lead to a greater cumulative relief of pain, resulting in a reduction in the use of opiates (and associated side-effects) by patients in a clinical setting. Additionally, cannabinoids can prevent the development of tolerance to and withdrawal from opiates, and can even rekindle opiate analgesia after a prior dosage has become ineffective.

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Novel research suggests that cannabis may be useful in the treatment of problematic substance use. These findings suggest that increasing safe access to medical cannabis may reduce the personal and social harms associated with addiction, particularly in relation to the growing problematic use of pharmaceutical opiates. Despite a lack of regulatory oversight by federal governments in North America, community-based medical cannabis dispensaries have proven successful at supplying patients with a safe source of cannabis within an environment conducive to healing, and may be reducing the problematic use of pharmaceutical opiates and other potentially harmful substances in their communities.


Evidence is growing that cannabis can be an effective treatment for chronic pain, presenting a safe and viable alternative or adjunct to pharmaceutical opiates. Addiction to pharmaceutical opiates has been noted by the medical community as one of the common side-effects of extended use by patients (such as those suffering from chronic pain), and a growing body of research suggests that some of the biological actions of cannabis and cannabinoids may be useful in reducing this dependence. Therefore cannabis has the potential to both relieve suffering for those suffering from chronic pain, and to reduce morbidity and mortality often associated the use and abuse of pharmaceutical opiates.

Since both the potential harms of pharmaceutical opiates and the relative safety of cannabis are well established, research on substitution effect suggests that cannabis may be effective in reducing the use and dependence of other substances of abuse such as illicit opiates, stimulants and alcohol. As such, there is reason to believe that a strategy aiming to maximize the therapeutic potential benefits of both cannabis and pharmaceutical cannabinoids by expanding their availability and use could potentially lead to a reduction in the prescription use of opiates, as well as other potentially dangerous pharmaceutical analgesics, licit and illicit substances, and thus a reduction in associated harms. The resulting public health benefits would include lower rates of alcohol-related automobile accidents, less domestic violence, reductions in drug-related crimes such as break-ins and petty theft, and reduced drug and alcohol-related morbidity and mortality.

International experience appears to support this premise. A recent report by the European Monitoring Center for Drugs and Drug Addiction shows that the Netherlands long-time policy of de facto cannabis decriminalization has resulted in some of the lowest drug-induced death rates in Europe, while countries with more severe cannabis laws and drug policies, such as Norway and Sweden, rank among the highest (EMCDDA 2009). Despite such compelling evidence, much of the world’s current and long-standing prohibitionist approach to cannabis continues to act as a barrier to these potential personal and public health benefits, and to criminalize otherwise law-abiding citizens as well as many critically and chronically ill patients.

Community-based dispensaries have emerged as a disjointed but effective social movement focused on the principles of harm reduction and human rights. Although they remain largely unregulated or even illegal in much of Canada and U.S., these dispensaries have been successful in establishing a safe and consistent supply of medical cannabis, advocating for patient rights, and adding to society’s knowledge and understanding of the therapeutic potential of cannabis through scientific research.

Additionally, evidence suggests that they are reducing the problematic use of opiates, alcohol and other substances in their communities. If we are to ever benefit from drug policies based on science, reason and compassion, national governments will need to abandon the misinformation that underscores drug prohibition, and to start promoting and supporting research into cannabis and cannabinoids as both a relatively safe and effective medicine in the treatment of chronic pain and other serious medical conditions, and as a potential “exit drug” for problematic substance use.