If Cannabis Should Meet Fibromyalgia

By John Quintner

Down through the ages Indian hemp (cannabis) spread from land to land. In China it was during the Wei dynasty that the famous physician Hoa Tho was able to prepare from it the sedative “Mario” which could very quickly throw the patient into so profound a sleep it was “as if he had drunk himself to death.” From: “Triumph Over Pain” by René Fülöp-Miller, 1938: 23

Various cannabis preparations are still widely used throughout the world, mainly for recreational purposes. But, as James Austin (2006) points out: Marijuana is often the first “herb” to lure innocents through the gate and down the garden path toward major “theobotanicals.”

Almost half of all 18-year-olds in the United States and in most European countries admit to having tried marijuana one or more times. Some have suggested that perhaps up to 10% of that teenage group become regular users (Iverson, 2003).

In recent years concerted political efforts have been made in many countries to legalise the growing and prescribing of cannabinoids for specific medical conditions. Fibromyalgia has been included as one of a number of chronically painful conditions in which cannabis might be indicated: http://www.webmd.com/fibromyalgia/guide/fibromyalgia-and-medical-marijuana

The particular constellation of symptoms to which the name fibromyalgia has been attached exists in varying degrees of severity within all communities. These symptoms are non-specific and include widespread pain and tenderness, fatiguability, sleep disturbance, cognitive impairment, mood changes etc. When present together in various combinations they are currently understood as reflecting “polysymptomatic distress” (Wolfe et al. 2015). Self-diagnosis is not at all uncommon, through the agency of electronic media and support groups.

Indeed, this symptom cluster has been found in 2% (or more) of the general population (Vincent et al. 2013). According to the American College of Rheumatology, the “diagnosis” is most frequently made between the ages of 20 to 50. By the age of 80, approximately 8% of adults will meet the ACR criteria for fibromyalgia.

However, given that there is no objective marker or test for fibromyalgia, and it has been said that the condition can co-exist with any other painful condition, theoretically the label may be applied to many of the one in five members of the general population who report persistent pain and associated distress.

In the United States chronic pain is the most common reason given by patients reporting “medical use” of cannabis (Dyer, 2013). It follows that if fibromyalgia is listed as a “specific indication” for cannabinoids, considerable diagnostic “leakage” is bound to occur. Those who wish to continue to use “medicinal” cannabis for recreational purposes would not find it difficult to fulfil the “diagnostic criteria” for fibromyalgia.

What an enormous commercial market for cannabinoid preparations would be created!

In the words of Ware & Desroches (2014): The medical use of cannabis is not an end in itself; the patient demanding cannabis and refusing to consider other options may have motivations other than amelioration of pain and improvement in quality of life.

But is there any evidence that would justify the prescribing of cannabinoid preparations for those presenting with chronic pain and specifically for those diagnosed with fibromyalgia?

Three reviews of variable quality have been published (Martin-Sanchez et al. 2009; Lynch et al. 2011; Grotenhermen & Müller-Vahl 2012). Farrell et al. (2014) provided an overview of the first two reviews and also conducted their own literature review.

According to Farrell et al (2014): “… the effectiveness of cannabinoids in treating other chronic pain (e.g. fibromyalgia) is unclear and any benefit is likely to be modest. Mild to moderate adverse effects are often reported and long-term safety has not been established.”

So if unproven cannabinoids were to be legitimised as “treatment” for too-easy-to-diagnose “fibromyalgia”, it is not too difficult to foresee an iatrogenic disaster that could sideline the hard-earned reputation of scientific medicine.

References:

Austin JH. Zen-Brain Reflections. Cambridge, Massachussetts: MIT Press, 2006:301-302.

Dyer O. The growth of medical marijuana. Brit Med J 2013; 347:f4755.

Farrell M, et al. Should doctors prescribe cannabinoids? BMJ 2014; 348: 348:g2737. doi: 10.1136/bmj.g2737.

Grotenhermen F, Müller-Vahl K. The therapeutic potential of cannabis and cannabinoids. Dtsch Artztebl Int 2012; 109: 495-501.

Iversen L. Cannabis and the brain. Brain 2003; 126: 1252-1270.

Lynch ME, Campbell F. Cannabinoids fro treatment of chronic non-cancer pain. A systematic review of randomized trials. Brit J Clin Pharmacol 2011; 72: 735-744.

Martin-Sanchez E, et al. Systematic review and meta-analysis of cannabis treatment for chronic pain. Pain Med 2009; 10: 1353-1368.

Vincent A, et al. Prevalence of fibromyalgia: a population-based study in Olmsted County, Minnesota, utilizing the Rochester-Minnesota project. Arthritis Care Res (Hoboken) 2013; 65(5): 786-792.

Ware MA, Desroches J Medical cannabis and pain. PAIN Clinical Updates, 2014, XXII (3).

Wolfe F, et al. The use of polysymptomatic distress categories in the evaluation of fibromyalgia (FM) and fibromyalgia severity. J Rheumatol 2015; 42(8): 1494-1501.

Additional Reference:

Faculty of Pain Medicine, Australian and New Zealand College of Anaesthetists PM10: Statement on “Medicinal Cannabis” with particular reference to its use in the management of patients with chronic non-cancer pain, 2015