Is Cannabis an “Exit Drug” From Opioid Dependency?

byEliannaLev5 minutes

In recent years, the opioid crisis has become a grim reality across Canada. Last year, more than 2,800 people died as a result of overdose from prescription painkillers and illegal opioids.

Due to a massive rise in illicit fentanyl, officials are beginning to see that illegal opioids are just as big of a problem as prescription ones are. In fact, Health Canada’s Drug Analysis Service (DAS) announced at the end of 2017 that they saw a 2,000% rise in positive fentanyl tests from heroin they seized throughout the year.

Sometimes it feels like the crisis is deepening no matter what we do, but one avenue that’s being explored as a possible “exit drug” to opioid addiction is cannabis. Scientists say preliminary results show marijuana has the potential to play a major part in solving the opioid epidemic, but that more specific research is needed to arrive at a conclusive answer.

What Are Opioids & How Do They Work?

Opioids are primarily used to relieve pain for a wide range of conditions from post-traumatic stress disorder (PTSD) to cancer to post-surgery pain. You’ve probably heard of many of the opiates available:

  • fentanyl
  • codeine
  • morphine
  • oxycodone
  • hydromorphone

Opioids work by binding to opioid receptors in different regions of the brain, spinal cord and digestive system. When you exercise and feel that “runner’s high,” that’s the body’s natural opioids, called endorphins, kicking in to make you feel great with less pain.

Natural opioids also activate receptors in the midbrain, which is where our pleasure/reward circuit is located. That explains why opioid users feel euphoria and can have trouble stopping their opioid use. Synthetic opioids are much more powerful than our natural ones, which is why man-made opioids can lead to dependence and addiction.

Opiate withdrawal symptoms are also sometimes as intense as the addiction itself. Opioids affect a chemical called norepinephrine. The opioids depress the chemical’s expression, but the body keeps making it. So, when someone stops taking opioids, all of the norepinephrine is released at once causing nausea, vomiting, chills and diarrhea.

Generally, the first phase of treatment for opioid addiction and withdrawal is a medication such as methadone, which is actually an opioid, too.

How Does Cannabis Interact With the Body?

Like opioids, cannabis interacts with the body through a network of receptors called the endocannabinoid system (ECS). These receptors are found throughout the body—in many more places than opioid receptors are found—including the brain, spine and even reproductive organs. There are also endocannabinoid receptors in the midbrain, which is why people report pain relief, euphoria and relaxation after consuming cannabis.

The cannabinoids found in marijuana such as tetrahydrocannabinol (THC) and cannabidiol (CBD) are so close to our natural endocannabinoids that THC and CBD bind to our ECS just as our internal compounds do. Research is starting to show that having a balanced ECS and healthy level of cannabinoids is important for overall good health. Topping up internal cannabinoids with phytocannabinoids from marijuana helps some people with a long list of health conditions from back pain to fibromyalgia to menstrual cramps.

Why Overdose Occurs With Opioids & not With Cannabis

The one location where there are more opioid receptors than there are cannabinoid receptors is the brainstem. The brainstem is where essential functions like breathing, blood pressure and heart rate are controlled by norepinephrine.

We know that opioids dampen the production of norepinephrine, which can eventually lead to withdrawal symptoms when the user stops taking opioids, but this is also why it’s possible to die from an opioid overdose. A high level of opioids will block so much of the body’s norepinephrine production that those essential functions will slow too much—sometimes to the point of death. But because there are barely any cannabinoid receptors in the brainstem, it’s impossible to die from ingesting too much marijuana.

Could People Take Cannabis Instead of Opioids?

So, if opioids and cannabis both effectively treat pain, could someone take cannabis instead of opioids? Could they consume some marijuana and only some of their opioid prescription to avoid becoming dependent? Could someone who’s already addicted to opioids use marijuana as an “exit drug,” to help wean them off of the pills and combat withdrawal symptoms? According to anecdotal evidence, the answer to all of these questions is yes—but is there any scientific proof?

A Vancouver-based scientist who studies cannabis’s effects on opioid use and addiction says more research is needed to fill in gaps in the scientific data. M-J Milloy is a research scientist at the BC Centre on Substance Use and an assistant professor of medicine at the University of British Columbia. For the last two decades, he’s participated in studies funded by a U.S. government research institute called the National Institute of Drug Abuse, surveying opioid users and those at risk of the disorder in Vancouver’s Downtown Eastside, a neighbourhood with high rates of drug use.

Milloy says there’s good preliminary data to suggest that cannabis can play a role as a “getaway drug” in helping people who struggle with the disease of opioid addiction. However, he stresses that more formal scientific work needs to be done before any conclusive points are made.

“We need to do the work experimentally through controlled trials to see what is effective and to try and develop treatment plans that incorporate medical cannabis,” he says.


Studies Seem to Back Marijuana as Exit Drug

In an exploratory study, which was recently submitted to a journal for review, Milloy and his team surveyed people starting methadone maintenance therapy. Methadone requires daily ingestion for the patient to gain full benefits of the treatment to successfully get off illegal opioids.

The researchers found that people who used cannabis on a daily basis while starting methadone treatment were 20% more likely to still be on the synthetic analgesic six months later. Though everyone’s different, addiction specialists generally maintain that people should stay on methadone for at least a year before beginning to taper off of it. As well, the longer they can stick with methadone maintenance, the greater their chances are in living an opioid-free life following treatment.

Milloy says evidence from animal-based research shows similar results that cannabis can help opioid withdrawal easier. Another study his research group published found declines in crack cocaine use among users trying to use cannabis to cut down on their crack use.

“That adds to the evidence pile that shows that for people with substance use disorders, cannabis is beneficial,” he says.

Marijuana-Opioid Studies of the Future

The next chapter in research should focus less on whether cannabis works and more on what kind of cannabis works, Milloy says. Examining the impact of different strains, and whether specific health benefits from cannabis are a result of THC, CBD or maybe under-examined terpenes are all areas that need to be explored.

“These are exciting questions to look at once we do this work in the light of day and not under the prohibition regime,” Milloy concludes.

Photo credit: Governor Tom Wolf