Medical cannabis in
ANOREXIA
Cannabidiol in cancer-induced anorexia
C
annabinoids, the chemical compounds found in cannabis, have been shown to improve appetite by acting on cell membrane receptors and altering neurotransmitter release. Nabilone, a synthetic cannabinoid, has been used to treat loss of appetite in cancer patients, along with cancer-induced nausea and vomiting (CINV). However, there is much uncertainty about its clinical effectiveness and evidence-based guidelines. This Rapid Response Report aimed to review the clinical effectiveness of nabilone in these areas. Guidelines associated with nabilone use in these areas were also examined. This was an update and upgrade of two previous Canadian Agency for Drugs and Technologies in Health (CADTH) reports examining the clinical effectiveness of and guidelines pertaining to the use of nabilone for the treatment of nausea and vomiting or anorexia in adults and adolescents (Ho C, MacDougall D: Nabilone for the Treatment of Nausea and Vomiting or Anorexia: A Re-
view of Clinical Effectiveness and Guidelines. Ottawa (ON): CADTH; 2019). This report made use of a literature search developed for a previous CADTH report. The original literature search was conducted in June 2017 on key resources, including PubMed, EMBASE, the Cochrane Library, University of York Centre for Reviews and Dissemination (CRD) databases and Canadian and major international health technology agencies, as well as a focused Internet search. Regarding the management of nausea and vomiting, the guideline recommended against the use of medical cannabis (MC) as first- or second-line treatment of CINV owing to limited comparison with first-line agents and known harms. With respect to using cannabis to improve appetite, however, their recommendations were more positive. One randomized controlled trial examined the efficacy and safety of 8 weeks of treatment with nabilone for patients with
advanced non-small cell lung cancer diagnosed with anorexia (Turcott JG, Del Rocío Guillen Núñez M, Flores-Estrada D, et al: The effect of nabilone on appetite, nutritional status, and quality of life in lung cancer patients: A randomized, double-blind clinical trial. Support Care Cancer 2018; 26(9):3029–3038). Patients who received nabilone increased their caloric intake (mean 342 kcal) compared to placebo, significantly increasing their daily intake of carbohydrates compared to placebo. However, there was no statistical difference in daily intake of proteins, fat or iron between the nabilone group or the placebo group. Despite this, the authors concluded that nabilone was an adequate and safe therapeutic option in the treatment of patients diagnosed with anorexia due to non-small lung cancer. Hallucination, drowsiness, dysphoria, depression, vertigo, dry mouth and lack of muscle coordination were also noted as possible side effects. —Diane Bracuk, CJMC Correspondent
Commentary Tamara Pryor, PhD, FAED, Denver, Colo., U.S.A.
EATING DISORDERS (EDS) are complex psychopathologies that present clinical challenges for many reasons. A major one is that EDs often co-occur with a substance use disorder (SUD). This includes cannabis abuse, which can begin before, concurrently with or after the onset of an ED. Given this, our clinic uses an integrative model in treating the SUD along with other ED symptoms, such as anxiety, obsessivecompulsive disorder and depression. Another challenge is that individuals with anorexia are empowered by resisting the temptation of eating. Therefore, the appetite-stimulating properties of cannabis can’t necessarily overcome the neurobiological issues that are also intimately involved with their ED. That being said, medical cannabis (MC) might be a helpful tool for some people in conjunction with therapies such as cognitive-behavioural therapy (CBT). There are three primary strains of cannabis: sativa, indica and hybrids. Sativa is the activating strain of cannabis that tends to energize the user and produce the “high.” It can be used to relieve the symptoms of depression, fatigue and mood disorders. Indica is a more sedating strain that produces relaxation and full-body effects and is preferred by the majority of our ED patients. Hybrids are varying functions of these two strains that are thought to balance the positive effects of both. One patient reported that MC helped slow down her mind, allowing her to observe her irrational thoughts sur16 • CANADIAN JOURNAL OF MEDICAL CANNABIS
rounding food. Food began to taste better, making her mealtimes an enjoyable experience. Addiction, of course, is a big concern. Between 7 and 9% of our ED patients who use cannabis show signs of addiction. With 364 legal dispensaries in Denver and 1,021 in Colorado, we can clearly expect that up to 50% of our ED patients are using. Moreover, testing an individual’s level of intoxication has proven to be a challenge due to the length of time THC takes to clear the body. How do we deal with this dilemma? We begin with a very extensive physical and psychological diagnostic assessment for the history of the ED and substance use/abuse. We need to determine whether the patient can participate in our program and is using edibles or tinctures or smoking. Is the patient using indica or sativa? Can we wean the patient off the higher levels of THC with a mix of CBD and a much lower percentage of THC? Finally, what withdrawal effects, such as irritability, insomnia and changes in appetite, need to be treated while still focusing on the patient’s compromised emotional and medical state due to the ED? There are many unanswered questions concerning MC use in ED. We have learned to practise “beginner’s mind” with an attitude of openness, curiosity and a lack of preconceptions or judgment when learning the adaptive function of both the ED and the cannabis use. Dr. Tamara Pryor is the executive clinical director and director of clinical research at EDCare in Denver.