How Cannabis Enables to Reduce Opioid Use in Chronic Pain Patients

Posted on 10/06/22 | Updated 06/10/22 Reading: 7 minutes


The therapeutic relevance of opioids in the treatment of severe acute pain and chronic pain associated with cancer is unquestionable. However, the use of opioids for the management of chronic non-cancer pain, the main reason why these drugs are currently prescribed in the world, is quite questionable, as it is associated with high rates of abuse and dependence and should not be used as first-line drugs in these cases.

The long-term use of opioids often causes a phenomenon of tolerance, that is, the patient needs increasingly higher doses to obtain therapeutic results. When the indication and prescription are not assertive, the result can be disastrous. The “opioid crisis” in the United States illustrates this context well: in 14 years, the country has summed more than 160 thousand deaths due to the overdose of these drugs.

Although the Brazilian scenario does not represent an opioid use crisis as it happens in countries like the United States and Canada, the current situation can be considered worrying, because in recent years, there has been an exponential (and epidemiologically disproportionate) increase in opioid prescriptions in Brazil.

According to a research conducted by FioCruz in partnership with the Johns Hopkins Bloomberg School of Public Health and the Universidade Estadual do Rio de Janeiro (UERJ), this increase was 465% during the period from 2009 to 2015. In absolute numbers, this means that the prescriptions jumped from 1.6 million to 9 million in the country.

Scholars on the subject speculate that the collapse of the opioid industry in developed countries has stimulated pharmaceutical companies in the industry to migrate their investments to developing countries. In this scenario, curiously, the oxycodone (the main opioid associated with the US opioid crisis), unlike other psychoactive drugs, such as antipsychotics and sedatives, is not considered a controlled substance. It is sold in pharmacies in the country with a prescription-only medicine, the same used for antibiotic and antihypertensive drugs. This is shocking, isn’t it?


>>>Read this article about this in Superinteressante sobre O Remédio Mais Perigoso do Mundo.


The good news is that medical Cannabis has been consolidated as a safe and effective strategy in the treatment of chronic pain associated or not with cancer. This contributes very effectively to the quality of life of patients and, at the same time, to the reduction in the use and even suspension of use of opioids. Read on and find out why.


The “opioid crisis” and the risk of overdose

Opioid drugs are based on opium, a component extracted from the poppy. Among its derivatives are substances such as morphine and heroin. Opioids have become a fever in the United States since the 1990s, largely due to the aggressive and technically unfair marketing of pharmaceutical companies in the industry.

With the volume of consumption, the pharmaceutical industries have earned a lot since then. On the other hand, during the period from 2000 to 2014, the country recorded more than 160 thousand deaths due to overdosing on these substances. Dizziness, lethargy, paranoias and respiratory depression are some symptoms of overdosing of these drugs.

Here in Brazil, something similar happens with the chronic use of benzodiazepine drugs, typically used to treat problems such as anxiety and insomnia. Although they have less potential to cause an overdose, benzodiazepines can also generate chemical dependency and withdrawal crises, making it difficult to wean medications.

Designing strategies to discontinue the use of certain medications is essential to achieve better results and better quality of life for patients. 

In this regard, medical Cannabis has been consolidating itself as a powerful agent capable of combining therapeutic effects and helping to reduce the use of opioids, considering the potential of substances such as CBD (cannabidiol) and THC (tetrahydrocannabinol) to modulate painful perceptions related to pain, and reduce the intensity and frequency of painful stimuli.


CBD and THC: pain relief and reduced use of opioids

In addition to acting in the relief of chronic pain, the phytocannabinoids CBD and THC act as adjuvants in weaning strategies for patients who use opioids, antidepressants, anxiolytics, anticonvulsants, antipsychotics, among other psychotropic drugs.

>>> Check out this study of Lucas, P. & Walsh, Z. Medical cannabis access, use, and substitution for prescription opioids and other substances: A survey of authorized medical cannabis patients. Int. J. Drug Policy 42, 30–35 (2017).

Cannabinoids also have properties that help to fight common adverse effects of these medications, such as irritability, insomnia, nausea, lack of appetite, constipation and fatigue. 

Specifically in relation to opioids, it is interesting to note that there is a synergic effect in the association with cannabinoids, preventing the development of tolerance to opioids and, therefore, avoiding the need to increase the dosage.


>>> We recommend reading these two publications about the topic: 


As for the analgesic properties of phytocannabinoids, it is important to highlight the THC potential to modulate unpleasant perceptions related to pain, as it is a partial agonist of CB1 endocannabinoid receptors, widely present in the motor sensitive cortex and amygdala. In addition, THC is a valuable antispasmodic and muscle relaxant, being useful in cases of chronic pain associated with spasticity. It is also important to note that the psychotoxic potential of THC is minimal in an assertive context of prescribing this phytocannabinoid – unlike opioids, of which psychotoxic potential and risk of overdose are significantly higher.


Scientific evidence

Several studies prove the efficacy of medical Cannabis in relieving pain as well as in reducing the use of opioids. 

A research conducted in 2020 by the Society of Cannabis Clinicians in Sevastopol, United States, evaluated 525 patients who used cannabinoids in combination with opioids, which were prescribed for at least three months to treat chronic pain. The results showed that:

  • 40% of patients were able to completely discontinue opioids;
  • 45% of patients were able to partially reduce opioids use;
  • 65% of patients were able to keep reducing opioid dosage for more than one year;
  • 48% of patients were able to reduce the pain perception index from 40% to 100%.

Another study that brought promising results was carried out by University of Victoria, in Canada. 1,145 patients were evaluated at 21 medical clinics across the country. Of this total, 28% used opioids and started treatment associated with cannabinoids. Six months after the experiment, the number of opioid users dropped to 11%, with the average daily dosage decreasing from 152 mg to 32 mg equivalent of morphine.

These results allow us to conclude that cannabinoid derivatives are an effective strategy, both from the therapeutic point of view of chronic pain and from the point of view of reducing the use of opioids, which brings better results to patients and prevents that the indiscriminate prescription of certain medications become serious public health problems.


If you wish to include Cannabis-based products in your therapeutic arsenal, contact us and join our global community of studies in Endocannabinoid Medicine!


gigantes farmacêuticas investem em Cannabis medicinal



Peixoto, LS et. al. Ansiedade: o uso da cannabis sativa como terapêutica alternativa frente aos benzodiazepínicos / Anxiety: the use of cannabis sativa as an alternative therapy in front of benzodiazepinics. Brazilian Journal of Development, Curitiba, v. 6, n. 7, jul. 2020.

Purcell C, Davis A, Moolman N, Taylor SM. Reduction of Benzodiazepine Use in Patients Prescribed Medical Cannabis. Cannabis Cannabinoid Res., 2019.


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