Cancer pain is one of the most common symptoms of cancer. Despite advances in pain management and cancer treatments, cancer pain still manifests in 39% of all cancer patients and 51% of those with advanced cancer in the world. [1]

 

Cannabis’s therapeutic effects have been well documented for years, albeit never been used clinically in a definitive manner. The growing progressive view on cannabis sparked a debate on its role in managing cancer pain.

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What is cancer pain?

 

Cancer pain is a complication of cancer that is often chronic because of the progressive nature of the disease. Cancer pain is directly caused by tissue damage or a side effect of cancer treatments such as chemotherapy and radiotherapy [2].

 

There are several types of cancer pain, and it’s important for a doctor to recognise them because treatments will mainly be based on the cause of pain.

 

  1. Pressure pain: The pressure of the growing tumor causes this pain. The tumor could hit pain-sensitive structures [3].

 

  1. Refractory pain: This type of pain can’t be managed by medication alone. Some refractory pain can be neuropathic pain or pain, which stems from faulty nervous system signals [4].

 

What are the current treatment options for cancer pain?

 

Cancer pain can be managed by medications 90% of the time [5]. In general, these are the prescribed medications for cancer pain. It can either be a combination or sole use of the following drugs:

 

  • Analgesic: Aspirin, paracetamol, and non-steroidal anti-inflammatory drugs can be taken for mild types of cancer pain.

 

  • Anti-nausea medications: These are prescribed, especially if the cancer treatment involves opioids as the latter can cause nausea and vomiting.

 

  • Opioids: For severe types of pain, opioid analgesia is recommended.

 

  • Adjuvant drugs: Refer to anaesthetics, antiarrhythmics, antiepileptics, corticosteroids, muscle relaxants, and nitrous oxide medications.

 

In some cases, in combination with medications, doctors prescribed pain treatment alternatives such as:

 

  • Physical techniques: This refers to physical therapies, relaxation of the muscles, nerve blocking, and surgery.

 

  • Psychological treatment: Treatments like family therapy, hypnosis, psychotherapy, stress-relieving techniques, and so on.

 

  • Social therapy: In combination with medication, social therapies like support groups helps too.

 

[2]

 

Can medical cannabis help in treating cancer pain?

The scope of research in using medical cannabis for cancer pain mostly tackles cannabis’s cannabinoids or Phyto-compounds unique to this plant. Two of the most investigated cannabinoids on the subject are CBD (cannabidiol) and THC (tetrahydrocannabinol).

 

The American National Cancer Institute (NCI) highlighted in one of their papers that CBD has the potential to soothe some of the side effects of chemotherapy, such as:

 

  • Lack of appetite
  • Nausea and vomiting
  • Pain

[6]

 

In a ground-breaking study featuring cancer pain, they found that the combination of opioids and THC-CBD extract showed better results than treating pain with opioids alone [7]. Another study in 2013 shared similar results in THC-CBD oral sprays, although the study recommends further investigations [8].

 

In a review of 119 patients where 5 have cancer pain, a team of analysts found that THC mimics codeine’s effect in managing pain [9]. Another recent study of 11 randomised controlled trials in chronic neuropathic pain showed that cannabinoids gave slightly significant changes in pain scores [10].

 

Some studies observed that cannabinoids gave distinct but manageable side effects. For example, in a study concerning 43 randomised controlled trials, patients showed beneficial signs of cannabinoid treatment, but some developed a risk of gastrointestinal side effects [11].

 

A randomised study of 117 patients using either THC, THC-CBD combination, or placebo, showed some good results concerning refractory cancer pain. There was a “modest” improvement in pain scores on the THC-CBD combination. Specifically, there was a 30% reduction in pain from 43% of the subjects [12].

 

While inconclusive for now on whether CBD and THC can truly moderate cancer pain, researchers nod to the fact that these cannabinoids have huge potential. Cannabis as a treatment for cancer pain warrants a trip to a specialist if you’re interested in going on that treatment route.

 

Disclaimer: This is not an inducement to use Medicinal Cannabis. Medical Cannabis doesn’t work for everyone, and it may not work for you. How Cannabis affects a person depends on many things, including their size, weight, age and health, dosage and tolerance, and the results can vary. Some people may experience side effects when taking Cannabinoid medication. The information provided by CDA Clinics is for educational and informational purposes only. For medical advice, please check with your doctor and request a referral.

 

Endnotes:

 

  1. van den Beuken-van Everdingen MH, et al. 2016. Update on prevalence of pain in patients with cancer: Systematic review and meta-analysis. Available at: https://pubmed.ncbi.nlm.nih.gov/27112310/

 

  1. Health Engine. 2006. Cancer Pain. Available at: https://healthengine.com.au/info/cancer-pain-2#:~:text=Cancer%20pain%20is%20a%20common,treatment%20(chemotherapy%2C%20radiotherapy)

 

  1. American Cancer Society. 2019. Facts about Cancer Pain. Available at: https://www.cancer.org/treatment/treatments-and-side-effects/physical-side-effects/pain/facts-about-cancer-pain.html

 

  1. Esin, E and Yalcin, S. 2014. Neuropathic cancer pain: What we are dealing with? How to manage it? Available at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4000251/

 

  1. Cancer Council Victoria. N.D. Overcoming Cancer Pain. Available at: https://www.cancervic.org.au/living-with-cancer/common-side-effects/overcoming-cancer-pain/overcoming-cancer-pain-overview.html

 

  1. A. N.D. Cannabis and Cannabinoids (PDQ®)–Health Professional Version. Available at: https://www.cancer.gov/about-cancer/treatment/cam/hp/cannabis-pdq

 

  1. Johnson, J. et al. 2010. Multicenter, Double-Blind, Randomized, Placebo-Controlled, Parallel-Group Study of the Efficacy, Safety, and Tolerability of THC:CBD Extract and THC Extract in Patients with Intractable Cancer-Related Pain. Available at: https://www.jpsmjournal.com/article/S0885-3924(09)00787-8/fulltext

 

  1. Johnson, J. et al. 2013. An Open-Label Extension Study to Investigate the Long-Term Safety and Tolerability of THC/CBD Oromucosal Spray and Oromucosal THC Spray in Patients With Terminal Cancer-Related Pain Refractory to Strong Opioid Analgesics. Available at: https://www.jpsmjournal.com/article/S0885-3924(12)00439-3/fulltext

 

  1. Campbell FA, Tramèr MR, Carroll D, et at. 2001. Are cannabinoids an effective and safe treatment option in the management of pain? A qualitative systematic review.Available at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC34324/

 

  1. Meng H, Johnston B, Englesakis M, et al. 2017. Selective cannabinoids for chronic neuropathic pain: A systematic review and meta-analysis. Available at: https://journals.lww.com/anesthesia-analgesia/fulltext/2017/11000/selective_cannabinoids_for_chronic_neuropathic.32.aspx

 

  1. Aviram J, Samuelly-Leichtag G. 2017. Efficacy of cannabis-based medicines for pain management: A systematic review and meta-analysis of randomized controlled trials. Available at: https://pubmed.ncbi.nlm.nih.gov/28934780/

 

  1. Johnson JR, Burnell-Nugent M, Lossignol D, et al. 2010. Multicenter, double-blind, randomized, placebo-controlled, parallel-group study of the efficacy, safety, and tolerability of THC:CBD extract and THC extract in patients with intractable cancer-related pain. Available at: https://pubmed.ncbi.nlm.nih.gov/19896326/