Nabilone for Chronic Non-Cancer Pain

Abstract

What Is the Issue? Chronic pain is pain that lasts beyond 3 months. Chronic non-cancer pain conditions include osteoarthritis, low back pain, musculoskeletal pain, fibromyalgia, and neuropathic pain. Approximately 1 in 5 people in Canada live with chronic pain. Nabilone (a cannabinoid) is indicated for the management of severe nausea and vomiting associated with cancer chemotherapy. Nabilone is also used in the management of chronic non-cancer pain. It is important to understand the potential benefits and harms of nabilone in people living with chronic non-cancer pain to support decision-making. What Did We Do? We sought to identify, summarize, and critically appraise literature comparing the clinical effectiveness of nabilone and placebo or alternative pharmacological options. We also searched for evidence-based guidelines that provide recommendations about the use of nabilone for the treatment of chronic non-cancer pain. We searched key resources, including journal citation databases, and conducted a focused internet search for relevant evidence published since 2015. One reviewer screened articles for inclusion based on predefined criteria, critically appraised the included studies, and narratively summarized the findings. What Did We Find? We found 1 overview of reviews and 2 systematic reviews that assessed the clinical efficacy and safety of nabilone for the treatment of chronic non-cancer pain. The evidence on the clinical efficacy of nabilone was mixed with some studies reporting an improvement in pain in those treated with nabilone versus placebo or active comparators and other studies reporting no difference between groups. Adverse events were more common in people living with chronic non-cancer pain who received nabilone than those who received placebo, ibuprofen, or amitriptyline. Adverse events were more common in those who received dihydrocodeine or gabapentin than nabilone. It is uncertain if nabilone is an effective treatment for people living with chronic non-cancer pain due to the varied results and methodological limitations of the included studies. We found 1 guideline that included a recommendation specific to nabilone and 2 guidelines that included recommendations on the use of cannabinoids in general. One guideline recommends against the use of nabilone for chronic pain, 1 guideline recommends offering a trial of non-inhaled cannabinoids (such as nabilone) for people living with chronic pain, and 1 guideline suggests cannabinoids be avoided in people with osteoarthritis and low back pain and discussed with people with neuropathic pain. What Does This Mean? Due to the uncertainty of the clinical evidence, decision-makers may wish to consider other factors such as costs, equity, and patient values and preferences when making decisions on the use of nabilone for people living with chronic non-cancer pain. Future high-quality, longer-term (e.g., RCT with follow-up studies) studies are needed to understand the efficacy and safety of nabilone for the treatment of people living with chronic non-cancer pain.