Cannabis, CBD and pain: what the trials show

In pain, the placebo effect is large: some participants get better whatever they receive. Only trials that compare CBD with a placebo, blinded, can tell whether it does anything more. The strongest ones all give the same answer.

In the Danish Vela trial, 22% of patients on CBD and 21% on placebo saw their pain fall by more than 30 mm out of 100. Sleep, anxiety and depression did not change either. The Brazilian CANOA trial tested a full-spectrum cannabis oil in knee osteoarthritis: both groups improved equally, and secondary outcomes, including sleep, did not differ.

The Cochrane review updated in 2026 pooled 21 trials and 2,187 participants with neuropathic pain, the kind that comes from nerve damage. It finds no clear evidence of an effect for THC-dominant medicines or for CBD-dominant ones. Products combining THC and CBD slightly increase the share of patients with 30% pain relief, with low certainty and an effect the authors judge not clinically relevant.

Across all cannabinoids, a meta-analysis of 65 trials and 7,017 participants, published in 2023, measures a drop in chronic pain of 0.43 points on a 10-point scale. That is below the threshold the authors consider noticeable to a patient, and the gain comes with more side effects. In 2021, the International Association for the Study of Pain (IASP) concluded that it could not endorse the general use of cannabinoids to treat pain, for lack of good-quality evidence.

French law classes as a medicine any product "presented as having curative or preventive properties with regard to human diseases", under article L5111-1 of the Public Health Code. This is the medicine by presentation rule: an oil sold "for pain" becomes an unauthorised medicine, whatever it contains. MILDECA, the French government's drug agency, points out that CBD products cannot make therapeutic claims, on pain of criminal penalties.

Each product family has its own text:

A CBD cosmetic can therefore talk about the skin: moisture, texture, how it feels during a massage. It cannot talk about joints, muscles or pain, which fall outside the definition of a cosmetic. Regulation (EU) No 655/2013 also requires every cosmetic claim to rest on adequate and verifiable evidence. Our guide to assessing a CBD cream or balm sets out how to read a label.

Cannabis-based medicines have nothing to do with CBD products sold in shops. They may contain THC, are prescribed by a doctor and monitored by the ANSM, the French medicines agency. The order of 16 October 2020 set the five situations of the French trial programme, two of which concern pain: "neuropathic pain refractory to accessible (drug or non-drug) therapies" and "painful spasticity in multiple sclerosis".

The trial programme ended on 31 December 2024. According to the ANSM page, updated in April 2026, patients already enrolled continue their treatment in a transition phase, which will end three months after the French National Authority for Health publishes its opinion. The future framework reserves these medicines for cases where existing treatments have failed, with the first prescription made in hospital. The timetable is tracked in our update on medical cannabis.

The only authorised CBD medicine, Epidyolex, is indicated for rare childhood epilepsies, not for pain.

A CBD product does not replace a pain treatment. A few markers help avoid bad surprises:

• Swallowed, CBD interacts with medicines. It is broken down by liver enzymes that also process many treatments; the interactions are explained in CBD's grapefruit effect. Talk to your doctor or pharmacist, especially if you take an anticoagulant or an anti-epileptic.
• A label that promises an effect on pain is a warning sign, not a guarantee: the seller is not following the law.
• The certificate of analysis tells you what the product contains, CBD and THC included. Our guide to reading a certificate of analysis goes through each line.

Pain that lasts, gets worse or keeps you from sleeping warrants a medical appointment. Your GP can look for a cause and, if needed, refer you to a specialist pain clinic. Conditions often linked to CBD are covered one by one in our articles on osteoarthritis and fibromyalgia.