Does the ratio of CBD to THC matter when treating chronic pain? This week’s TRUCE Medical Minute will review a recent study published in the journal Pain. It was a fairly elegant study performed in the Netherlands. The authors recruited 20 female patients with fibromyalgia who had not used cannabis recently. They then gave the patients 4 dried-flower cannabis varieties with different ratios of THC:CBD on separate occasions—(1) 22:1, (2) 6.3:8, (3) 1:9, and (4) placebo (cannabinoids had been extracted). All the patients were given a single inhalation via a flower vaporizer. The researchers measured blood concentrations of the cannabinoids.

The researchers then subjected the patients to a pressure pain test (pinching the skin between thumb and index finger) and an electrical pain test (electrodes on the shin). This way, a reliable pain stimulus could be given to each patient. Here’s the interesting finding: none of the THC:CBD ratios were more effective on the pain tests than placebo. When given the placebo, most patients reported some mild pain relief.

Drug high was associated with more tolerance to the pinch and electrical tests, however. CBD increased blood concentrations of THC, but lowered the pain-relief when combined with THC.

This was a small study (like all cannabis studies) but in my opinion it’s important when we’re talking about using cannabis to treat chronic pain. When I counsel patients, I often say that cannabis alone (CBD or THC) is a mild pain reliever. This study suggests that the ratio of THC:CBD may not matter when using cannabis for chronic pain, or CBD could counter-act the effect of THC since the level of perceived high was correlated with pain-relief.

Interestingly, the placebo group had statistically-significant levels of pain-reduction. Since pain is often a complex problem, co-mingled with mood and emotion, the placebo effect can be very powerful. If your mood is better when using cannabis, your pain levels will be lower and you’ll be able to function better.

In holistic terms, cannabis can be used to open the door of well-being. Better mood can lead to better diet, relationships, sleep, exercise and then improvement of pain. Cannabis can put you on the pathway to wellness. It doesn’t appear to be a magic bullet, but a piece to the overall puzzle of living life well.

1. Tine van de Donk et. al. Pain. 2019 Apr; 160(4): 860–869.

Scott Allen, MD
Board Certified Anesthesiologist
Fellowship Trained in Transplant Anesthesia
Practicing in St. George, UT