By John Brunstein
18 Apr 2017
A physiotherapist here with a question for Dr. John: I have a 66 year-old, female patient with recent onset of small-fibre peripheral neuropathy. Her chief complaint is severe foot pain (bilateral, 9 out of 10). She describes the pain as burning, tingling, pins and needles, sharp pain, and severe paresthesia at times. She cannot tolerate the gabapentin as prescribed by the neurologist. She is now on amitriptyline–the side effects are less but present. On examination, she has swollen, cold feet with reduced range of motion, poor balance and an abnormal wide-stance gait. She has started using a cane as a balance aide. I have given her an exercise program to restore or maintain her balance and gait. She is asking me about marijuana to reduce her symptoms especially the pain. Her doctor is not well-versed on uses of medical marijuana.
Thanks for the question. As always, the first part of our reply is that we have to clearly state that only an appropriately licenced medical professional, such as your patient’s physician, can legally prescribe medical marihuana in Canada. What we can do in this case however is tell you that there is legitimate, well conducted, peer reviewed medical research which suggests that particularly for peripheral neuropathic pain such as described by your patient, that cannabis can be as effective or better than gabapentin or amitriptylene. One such publication which is publically accessible online is:
Wilsey B et. al. Low Dose Vaporized Cannabis Significantly Improves Neuropathic Pain J Pain. 2013 Feb; 14(2): 136–148.
This is a technical article and as such may be somewhat unapproachable to your patient. If that’s the case, some of its relevant findings can be briefly summarized as:
We would suggest that your patient should approach her physician with this information (in its entirety, as the physician will most likely want to obtain and read our citation; perhaps consider printing and taking our response here to the physician). Based on review of this and perhaps other subreferenced literature, her physician may well decide that cannabis may be worth trying for your patient. If s/he does so, we would further suggest your patient keeps her physician involved in the selection of a couple of different cannabis strain types (i.e. one each primarily THC, primarily CBD, and one THC/CBD balanced strain). This information is available for product lots from legitimate licensed producers here in Canada. (As always, we strongly advise against obtaining cannabis from any other sources, as with these there are no guarantees of quality control, demonstrated lack of pathogens and pesticides, or assurance stated active ingredient levels are accurate). We’d also suggest that the described delivery method (vaporization, as opposed to smoked or edibles) be employed. With these few cannabinoid strains in hand spanning across the three major forms of chemotypic makeup, and an appropriate delivery system, we would then suggest active physician / patient involvement in the careful dose titration of each of the three to identify if one of the three, at an appropriate dose level, can provide superior pain relief without undue side effects.
Certainly, based on available legitimate medical research, it seems to have likely potential in this case. We wish your client the best in her quest for a better treatment of her condition, and would be more than happy to answer any technical questions her physician might want to pose to us in better understanding the current status of research into cannabinoid therapies for neuropathic pain.
Dr. John Brunstein, Ph.D.