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  • Cannabis can sometimes be used as a method of chronic pain relief, but there is a lot about cannabis’ health benefits and associated risks that researchers still don’t understand.
  • New research found that some cannabis products containing THC and CBD components may help with the short-term improvement of chronic pain.
  • The findings also suggest a risk of sedation and dizziness associated with use, and there needs to be more data on the long-term impact.

Many people experience chronic pain or pain that lasts for an extended period. Experts are constantly researching new methods of pain relief and new medication options. One area of interest is the use of cannabis products as a method of pain relief.

A recent systematic review published in the Annals of Internal Medicine found that cannabis products might help treat chronic pain in the short term. However, medical professionals need to weigh this against the potential drawbacks of increased dizziness and sedation. It is also unclear whether or not these products are helpful in the long term.

Chronic pain lasts for months or longer, and millions of adults in the U.S. experience chronic pain. Because many people experience chronic pain, experts are constantly working to evaluate potential treatments and therapies. As experts continue to research the medicinal uses of cannabis, one area of interest is how doctors could use it to treat chronic pain.

Cannabis is a plant, and people can use different plant portions to produce various products. The two main compounds of cannabis are cannabidiol (CBD) and tetrahydrocannabinol (THC).

Some products contain both THC and CBD. The CBD portion does not cause mind-altering effects, while the THC portion causes the high people to experience when they use cannabis. Some of these related products are available in the U.S., while some are not. Currently, the Food and Drug Administration has approved using two medications that contain THC: Marinol and Syndros.

This systematic review sought “To evaluate the benefits and harms of cannabinoids for chronic pain.” The term Cannabinoids refers to compounds that contain both THC and CBD.

Researchers used several databases to collect the studies they reviewed. They included studies written in English that addressed the use of cannabis products as a treatment for chronic pain. Specifically, the study involved a follow-up or treatment time of four weeks or more. The analysis included placebo-controlled randomized controlled trials and cohort studies where the use of cannabis had a concurrent control group.

They included a total of 25 studies in their analysis. Researchers examined the products used in the studies and looked at the THC-to-CBD ratio. Did the product contain a high THC amount and a low CBD amount, was the amount about equal or did the product have a low THC amount and a high CBD amount?

The results of the review were somewhat lacking. The data was insufficient for some products to determine if they effectively treated chronic pain. However, researchers did discover some findings that supported the effectiveness of cannabis products:

  • Synthetic oral products with a high THC-to-CBD ratio might contribute to short-term chronic pain relief.
  • Sublingual extracted cannabis products with almost equal THC-to-CBD proportions might be associated with short-term improvements in chronic pain.

However, they found that people who use these products might also experience an increased risk for dizziness and sedation, which doctors will need to weigh against the potential benefits. Overall, they also found that experts need to conduct more studies about the long-term outcomes of cannabis use.

Study author Marian S. McDonagh found the lack of data surprising. She explained:

“With so much buzz around cannabis-related products, and the easy availability of recreational and medical marijuana in many states, consumers and patients might assume there would be more evidence about the benefits and side effects. Unfortunately, there is very little scientifically valid research into most these products.”

Professor Winston Morgan, pharmacology and toxicology specialist with the University of East London, not involved with the study, noted the following to Medical News Today:

“For any new mediation it must improve on current treatments in terms of both efficacy and safety. For decades cannabinoids have promised but never quite deliver. This review which takes an interesting approach on the benefits and harms of cannabinoids for chronic pain, suggest that only moderate benefits can be gained with products with high THC ratios, but these are more likely to cause adverse effects. Sadly these adverse effects may also limit long term use.”

This systematic review yielded some helpful information. However, it also had several limitations. First of all, researchers made certain decisions during the review process that may have impacted the review results, such as how certain cannabis products were categorized. The methods of analyzing the data do have a risk of imprecision.

They were also unable to assess publication bias on many outcomes due to available data and did not include studies that weren’t written in English. Finally, different studies used different interventions, and some studies lacked details. For some products, there was simply inadequate evidence.

Researchers of the systematic review plan to update the review quarterly so that they can add new evidence as it emerges. Overall, this paper demonstrates some of the current understandings of cannabis and the need for further research. Doctors can examine reviews like this one to help guide their patients in the treatment of chronic pain.

Study author Devan Kansagara, MD, M.C.R explained:

“This new living evidence review is exactly the type of resource clinicians need to clarify for patients the
areas of potential promise, the cannabis formulations that have been studied and, importantly, the
major gaps in knowledge.”