A Role for Medical Cannabis in Combating the Opioid Epidemic

Drug overdoses and opioid-related deaths have reached epidemic proportions throughout the United States (1). Over the past 25 years or so, the number of opioid-related deaths (from prescription opioids including oxycodone, hydrocodone and methadone and heroin) quadrupled to more than 200,000 (2). In 2015 alone, opioid overdoses resulted in 33,901deaths (1, 2) and in 2016 nearly half of all opioid-related deaths involved prescription opioids (CDC). Today, opioid-related deaths in the US surpass combined deaths caused by both car accidents and guns annually (2, 3).

Cause of the Epidemic

While the exact causes of the current opioid academic are uncertain, a variety of factors including job loss, chronic unemployment, financial hardship and over-marketing/over-prescribing of opioids have been suggested. It is important to note, however that between 1981 and 2011 the number of opioid prescriptions in the US tripled from 76 million to 219 million per year (4). According to a recent survey, over 97 million people took prescription opioids in 2015 and of these, roughly 12 million used opioids without being directed by a doctor (5).  Interestingly, because of recent state legislative initiatives that restrict the opioid prescribing habits of physicians, the number prescription opioids deaths appeared to level off in 2011(6). However, since 2011 the number of heroin overdose deaths and those related to illegal “black market” synthetic opioids like fentanyl has skyrocketed (CDC) in many hard hit states like West Virginia, Pennsylvania and New Hampshire. This is because heroin and fentanyl are now much cheaper and more available than prescription opioids (6).

The current opioid epidemic is forcing many physicians to reevaluate their use of prescription opioids for pain control and to consider alternative pain management strategies. There is an emerging body of evidence that suggests that medical cannabis (smoked, vaporized or ingested) can effectively manage and control chronic non-cancer pain (6-9), reduce opioid consumption (10-15) and help to lower opioid overdose deaths (14, 15).

Medical Cannabis and Pain Management

There are numerous reports that show that smoked or vaporized medical marijuana (and cannabis extracts), used alone or in combination with opioids, can effectively treat chronic neuropathic pain, muscle pain associated with spasticity from Multiple Sclerosis and certain types of cancer pain (8,9). More important, these studies found that smoked/vaporized cannabis or its extracts induce few adverse side effects and are safe for use; even in chronic pain patients who take prescription opioids for pain management (7).

Cannabis Reduces Opioid Consumption and Lowers Overdose Deaths

Although cannabis is not approved as a treatment for pain in the US, there is new evidence from states where medical cannabis is legal that cannabis reduces opioid consumption in chronic pain patients. Several studies in the US and around the world showed that opioid use dropped by as much as 50% among chronic pain patients when they were given access to cannabis. (10, 11). Further, other studies with chronic pain patients showed that cannabis use—along with its opioid-sparring effect—enhanced patient executive cognitive performance (12). The observed improved cognitive functioning likely resulted from a 42% reduction in opioid use by these patients (12).

A study that researched the association between the existence of state medical marijuana laws and opioid overdose deaths from 1999 to 2010 found that opioid overdose deaths declined by as much as 25% in states that had medical cannabis laws in effect (14). Other research showed that reductions in opioid overdose deaths tend to improve in states where medical cannabis laws have been in effect the longest (15). For example, in California, where medical cannabis laws have been in effect since 1996, there has been a 33% drop in the number of opioid overdose deaths (14). Similar reductions were also observed in other legacy medical cannabis states such as Oregon, Colorado and the State of Washington (14,15).

Other Efforts

Several biotechnology and pharmaceutical companies are attempting to develop cannabis –derived drugs and mimetics that treat pain by binding to certain types of cannabis receptors found throughout the body (16). Removing cannabis’ psychotropic effects and preserving its pain-relieving benefits is the major objective for this new class of drugs (16). Although these drugs are still in early stages of development, using them rather than addictive opioids to manage chronic pain would be an important step in curbing opioid overuse and abuse.

A Path Forward

Physicians play a critical role in prescription drug misuse and abuse prevention. To that point, continuing medical education programs that help raise awareness and educate physicians about the benefits of cannabis for pain management represents and important first step to curb over-prescription of opioids. Further, ongoing political and financial support for recent federal initiatives (17) such as enhancing access to prescription drug monitoring using health information technology, formalized collaborative efforts between insurers, health care providers, and employers to combat opioid misuse and abuse and community-based programs like the national take-back initiative—which provides a safe, secure, environmentally-responsible plan for disposing of prescription opioids and educates the public about the potential for abusing and trafficking prescription medications—will also be critical. Finally, new federal and state legislation that offers counseling and medical solutions to treat opioid abusers rather than punish them will be vital to control America’s epidemic opioid crisis.


  1. Rudd RA, Seth P, David F, Scholl L. Increases in Drug and opioid-involved overdose deaths — United States, 2010–2015. MMWR Morb Mortal Wkly Rep. ePub: 16 December 2016. DOI: http://dx.doi.org/10.15585/mmwr.mm6550e1  Accessed October 23, 2017
  2. CDC. Wide-ranging online data for epidemiologic research (WONDER). Atlanta, GA: CDC, National Center for Health Statistics; 2016. Available at http://wonder.cdc.gov  Accessed October 23, 2017.
  3. Drug overdoes now kill more Americans than guns. CBS News 2016 https://www.cbsnews.com/news/drug-overdose-deaths-heroin-opioid-prescription-painkillers-more-than-guns/ Accessed October 23, 2017
  4. America’s opioid epidemic is worsening. The Economist (UK) 2017    https://www.economist.com/blogs/graphicdetail/2017/03/daily-chart-3  Accessed  October 23, 2017.
  5. Hughes A, William MR, Lipari RN, Bose J. Prescription drug use and misuse in the United States: results from the 2015 national survey on drug use and health. Substance Abuse and Mental Health Services Administration (SAMHSA) 2016 https://www.samhsa.gov/data/sites/default/files/NSDUH-FFR2-2015/NSDUH-FFR2-2015.htm  Accessed October 23, 2017.
  6. Katz J. Short answers to hard questions about the opioid crisis. The New York Times 20 https://www.nytimes.com/interactive/2017/08/03/upshot/opioid-drug-overdose-epidemic.html Accessed October 23, 2017.
  7. Jensen B, Chen J, Furnish T, Wallace M. Medical marijuana and chronic pain: a review of basic science and clinical evidence. Curr Pain Headache Rep. 2015; 19:50 doi: 10.1007/s11916-015-0524-x.
  8. Wilsey B, Marcotte, Deutsch R, Gouaux B, Sakai S, Donaghe H. Low-dose vaporized cannabis significantly improves neuropathic pain. J. Pain. 2013; 14:136-148.
  9. Andreae MH, Carter GM, Shaparin N, Suslov K, et al. Inhaled cannabis for chronic neuropathic pain: a meta-analysis of individual patient data J. Pain 2015; 16:1221-1232.
  10. Boehnke KF, Litinas E, Clauw DJ. Medical cannabis use is associated with decreased opiate medication: use in a retrospective cross-sectional survey of patients with chronic pain. J Pain. 2016; 17:739-744.
  11. Haroutounian S, Ratz Y, Ginosar Y, Furmanov K, Saifi F, Meidan R, Davidson E. The effect of medicinal cannabis on pain and quality-of-life outcomes in chronic pain: A prospective open-label study. Clin J Pain. 2016; 32:1036-1043
  12. Gruber SA, Sagar KA, Dahlgren MK, Racine MT, Smith RT, Lukas SE. Splendor in the Grass? A pilot study assessing the impact of medical marijuana on executive function. Front Pharmacol. 2016; 7: 355  eCollection 2016.
  13. Bradford AC, Bradford WD. Medical marijuana laws reduce prescription medication use in Medicare Part D. Health Aff (Millwood). 2016; 35:1230-1236.
  14. Bachhuber MA, Saloner B, Cunningham CO, Barry CL. Medical cannabis laws and opioid analgesic overdose mortality in the United States, 1999-2010. JAMA. Intern Med. 2014; 174:1668-1673.
  15. Kim JH, Santaella-Tenorio J, Mauro C, Wrobel J, Cerda M, Keyes KM, Hasin D, Martins SS, Li G. State medical marijuana laws and the prevalence of opioids detected among fatally injured drivers. Am J Public Health. 2016; 106: 2032-2037.
  16. Mintz CS, Fabrizio AJ, Nison E. Cannabis-Derived Pharmaceuticals. J. Comm. Biotechnol. 2015; 21:16-30.
  17. SAMHSA’s effort to fight prescription drug misuse and abuse. https://www.samhsa.gov/prescription-drug-misuse-abuse/samhsas-effort  Accessed October 23, 2017.

Treating Cancer-Related Symptoms with Cannabis

In the 1970s, purified and synthetic cannabinoids were being evaluated as palliative treatments for cancer related symptoms (1). One of the earliest recognized clinical indications for cannabinoids was cancer induced nausea and vomiting (CINV) [2].

A 1988 prospective open label trial found that inhaled cannabis effectively controlled CINV in 78% of 56 cancer patients who had inadequate control of nausea and vomiting with conventional anti-emetics (3). Also, a later report that evaluated 30 trials and over 1300 participants determined that synthetic THC molecules such as nabilone and dronabinol were more effective than conventional anti-emetics in controlling acute CINV (2). This led to the early approval of dronabinol and nabilone as treatments for CINV but their use as a treatment for CINV has not been widespread (2,3)

A quick search of the clinical trials site www.clinical trials.gov revealed that there are no US clinical trials currently underway to further evaluate the use of Cannabis as a treatment for CINV.  Moreover, there are no natural Cannabis products e.g. extracts, sprays etc, on the market today that have received US Food and Drug Administration (FDA) approval as a treatment for CINV.

Inhaled Cannabis, and extracts containing THC and CBD have been clinically found to be more effective in treating cancer-related neuropathic pain than placebo (3, 4) but their effectiveness compared with conventional pain medications is uncertain (2). Yet, despite this, GW Pharma’s Sativex® (an extract that contains 1:1 ratio of Δ-9-tetrahydrocannabinol (THC) and cannabidiol [CBD]) is an approved treatment for cancer-related pain in 27 countries outside of the US (5).

There are currently 4 US clinical trials in (various phases) that are underway to determine the effects on Sativex® on advanced cancer pain and chemotherapy-induced neuropathic pain (Table 1). Regulatory experts expect Sativex® to garner FDA approval for both indications.


  1. Guzman M, Duarte MJ, Blazquez C, et al. A pilot clinical study of Delta9-tetrahydrocannabinol in patients with recurrent glioblastoma multiforme. British Journal of Cancer 2006; 95:197-203.
  2. Tramer MR, Carroll D, Campbell FA, Reynolds DJ, Moore RA, McQuay HJ. Cannabinoids for control of chemotherapy induced nausea and vomiting: quantitative systematic review. BMJ 2002; 323:16-21.
  3. Bowles DW, O’Bryant CL, Camidge DR, Jimeno A. The intersection between cannabis and cancer in the United States. Critical Reviews in Oncology/Hematology 2012; 83:1-10
  4. Notcutt W, Price M, Miller R, et al.  Initial experiences with medicinal extracts of cannabis for chronic pain: results from 34 ‘N of 1’ studies. Anaesthesia 2004; 59:440-452.
  5. https://www.gwpharm.com/products-pipeline/sativex  Accessed July 12, 2017


THC, CBD and Multiple Sclerosis

The established immunomodulatory properties of certain cannabinoids, most notably Δ-9 tetrahydrocannabinol (THC)  and cannabidiol (CBD), suggested that they may be therapeutically useful to treat multiple sclerosis (MS) which is generally believed to be autoimmune neurological diseases. (1). To that point, from 2005-2009, clinical trials involving 1300 patients were conducted to assess the effects of Cannabis, cannabis extracts and synthetic THC on MS and MS-related muscle spasticity and pain. (2, 3).

The results of these studies showed that cannabis extracts containing different ratios of THC and CBD as well as THC and nabilone (synthetic THC) can improve MS-related symptoms of spasticity, pain and urinary incontinence.  (2, 3 ) Additional clinical studies led to the approval of GW Pharma’s Sativex® (1:1 ratio of THC: CBD) in 27 countries (not the US) as a treatment for MS spasticity (4).

At present, in the US, there are 15 late stage clinical trials in progress that are evaluating smoked/vaporized cannabis (2) and Sativex® (13) as treatments for MS and MS-related spasticity, pain and urinary incontinence (Table 1).

Based on GW Pharma’s success with Sativex® as a treatment for various MS indications in other countries, it is likely the company will receive approval as an MS treatment in the US.


  1. Giacoppo S, Mandolino G, Galuppo M, Bramanti P, Mazzon E. Cannabinoids: new promising agents in the treatment of neurological diseases. Molecules 2014; 19:18781-18816
  2. Zajicek JP, Apostu VI. Role of cannabinoids in multiple sclerosis. CNS Drugs 2011; 25:187-201
  3. Hazenkamp A GF. (2010) Review on clinical studies with cannabis and cannabinoids 2005-2009. Cannabinoids 5(special issue) 2010; 1-21.
  4. Zajicek JP, Hobart JC, Slade A, Barnes D, Mattison PG, Group MR. (2012) Multiple sclerosis and extract of cannabis: results of the MUSEC trial. Journal of Neurology, Neurosurgery, and Psychiatry 2012; 83:1125-1132.