Quality-controlled cannabis for non-cancer pain is quite safe

PainSci » bibliography » Ware et al 2015
updated Nov 22, 2019

Tags: pain, medications, good news, cannabis, self-treatment, treatment

Nine pages on PainSci cite Ware 2015: 1. Pain & Injury Survival Tips 2. The Complete Guide to Low Back Pain 3. The Complete Guide to Chronic Tension Headaches 4. The Complete Guide to Neck Pain & Cricks 5. Smoking and Chronic Pain 6. Complete Guide to Frozen Shoulder 7. A Rational Guide to Fibromyalgia 8. Marijuana for Pain 9. Weed works for pain—major new report

Photo by Jose Luis Sanchez Pereyra on Unsplash

PainSci notes on Ware 2015:

Although we already have many reasons to suspect that cannabis usage is very safe, the more data the better on this topic, and particularly in the context of treating non-cancer pain. The results are good news, and completely consistent with other evidence. Ars Technica:

Almost every news story one reads about the use of cannabis as a medical therapy contains some variation of disclaimer saying ‘more research is needed’ into the longterm safety of medical cannabis use. Now a tiny bit of that ‘more research’ has been published in the Journal of Pain. The headline result was that there was NO INCREASE IN THE NUMBER OF SERIOUS ADVERSE EVENTS in a group that used cannabis for chronic pain when compared to a group that did not.

It’s hard to overstate how significant that kind of safety level is for any medication that helps with pain. Even the mildest over-the-counter analgesics come with serious risks (see How risky are NSAIDS?). Cannabis is not risk free — this study did find evidence of non-serious adverse events — but the total absence of serious adverse events is a big deal.

(By the way, this science comes from Canada, which is where I come from. You’re welcome.)

original abstract †Abstracts here may not perfectly match originals, for a variety of technical and practical reasons. Some abstacts are truncated for my purposes here, if they are particularly long-winded and unhelpful. I occasionally add clarifying notes. And I make some minor corrections.

Cannabis is widely used as a self-management strategy by patients with a wide range of symptoms and diseases including chronic noncancer pain. The safety of cannabis use for medical purposes has not been systematically evaluated. We conducted a prospective cohort study to describe safety issues among subjects with chronic noncancer pain. A standardized herbal cannabis product (12.5% THC) was dispensed to eligible subjects for a one-year period; controls were subjects with chronic pain from the same clinics who were not cannabis users. The primary outcome consisted of serious adverse events (SAEs) and non-serious adverse events (AEs). Secondary safety outcomes included pulmonary and neurocognitive function and standard hematology, biochemistry, renal, liver and endocrine function. Secondary efficacy parameters included pain and other symptoms, mood, and quality of life. Two hundred and sixteen individuals with chronic pain were recruited to the cannabis group (141 current users and 58 ex-users) and 215 controls (chronic pain but no current cannabis use) from seven clinics across Canada. The median daily cannabis dose was 2.5g/d. There was no difference in risk of SAEs (adjusted IRR=1.08, 95% CI=0.57-2.04) between groups. Medical cannabis users were at increased risk of non-serious AEs (adjusted IRR=1.73, 95% CI=1.41-2.13); most were mild to moderate. There were no differences in secondary safety assessments. Quality-controlled herbal cannabis, when used by cannabis-experienced patients as part of a monitored treatment program over one year, appears to have a reasonable safety profile. Longer term monitoring for functional outcomes is needed.

PERSPECTIVE: This study evaluated the safety of cannabis use by patients with chronic pain over one year. The study found that there was a higher rate of adverse events among cannabis users compared to controls but not for serious adverse events at an average dose of 2.5g herbal cannabis per day.

original abstract †Abstracts here may not perfectly match originals, for a variety of technical and practical reasons. Some abstacts are truncated for my purposes here, if they are particularly long-winded and unhelpful. I occasionally add clarifying notes. And I make some minor corrections.

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