CBD LoveThe independent Australian guideSearch

CBD and inflammation

CBD reduces inflammation in lab and animal studies. In people, trials in inflammatory conditions and after exercise have mostly found no benefit.

Facts checked 13 November 20266 min readHow we research
Not enough evidence

The anti-inflammatory claim rests on lab and animal work; human trials in bowel disease, arthritis and exercise recovery (doses from 20 to about 600 mg a day) mostly found no benefit.

How we grade evidence

CBD reduces markers of inflammation in laboratory and animal studies, but that has not translated into proven benefits in people. When CBD has been tested in human inflammatory conditions, such as Crohn’s disease, ulcerative colitis and arthritis, and for muscle damage after exercise, it has mostly done no better than placebo.

Inflammation is the body’s response to injury or infection. It is part of many different conditions, from arthritis and bowel disease to skin problems, and each has its own causes and treatments. That is why “CBD reduces inflammation” is a marketing claim more than a medical one.

What the research shows

Laboratory and animal studies

A 2021 systematic review gathered 26 animal studies of cannabinoids and inflammation, 20 of them on CBD. In most, CBD lowered the levels of inflammatory signalling molecules called cytokines, and in many there were some improvements in the animals’ disease. THC alone did not lower these markers.1

These findings are real, but they are early-stage science:

  • Most treatments that work in mice fail in people. See how we grade the evidence.
  • The dose reaching the body is small. Only about 6% of a swallowed dose of CBD reaches the bloodstream when taken without food.2
  • The mechanism is unclear. CBD acts on many targets in the body. The World Health Organization noted in 2018 that “it is not clear which, if any, of these mechanisms are responsible” for any of CBD’s possible effects.2
  • Lab markers are not outcomes. A lower cytokine level in a blood test is not the same as less pain, fewer flare-ups or better function.

Human trials in inflammatory conditions

Condition Trial Result
Crohn’s disease Naftali 2017, 20 people, 10 mg twice a day for 8 weeks No difference from placebo in disease activity. Published as “Low-dose cannabidiol is safe but not effective”3
Ulcerative colitis Irving 2018, 60 people, CBD-rich cannabis extract that also contained THC, 10 weeks Remission in 24% on the extract and 26% on placebo. Some secondary measures favoured the extract in people who took enough of it45
Hand osteoarthritis and psoriatic arthritis Vela 2022, 136 people, 20 to 30 mg a day for 12 weeks No difference in pain from placebo6
Knee osteoarthritis Pramhas 2023, 86 people, 600 mg a day for 8 weeks No difference in pain from placebo; more liver enzyme rises7

A review of the Cochrane evidence on cannabis for Crohn’s disease and ulcerative colitis found five small trials with 185 participants. It concluded that “no firm conclusions can be made” about safety or effectiveness.4 Psoriatic arthritis is an inflammatory form of arthritis, and the trial that included it found no benefit at low doses.6 More detail is on our pages on IBS, Crohn’s and colitis and arthritis.

Inflammation after exercise

  • Female athletes. In a crossover trial, 24 well-trained women took CBD (5 mg per kg of body weight, three times: 2 hours before, straight after and 10 hours after) or placebo around a hard leg workout. There were no differences in inflammation, muscle damage or fatigue, and no faster return of strength.8
  • Trained athletes. In another crossover trial, 17 athletes took 60 mg of CBD or placebo after each session of a six-day training block. Neither CBD product changed performance or blood markers of inflammation. One marker of muscle damage fell with one of the two products in a subgroup of athletes, a finding that needs confirming.9

See CBD and sport.

COVID-19

A Brazilian randomised trial gave people with mild to moderate COVID-19, an infection with a strong inflammatory component, 300 mg of CBD a day for 14 days. CBD did not change the course of the illness.10 See CBD and COVID-19.

What doses were tested

Human trials in inflammatory conditions used 20 to 30 mg a day,6 300 mg a day,10 600 mg a day,7 and three doses of about 5 mg per kg (roughly 325 mg each for a 65 kg person) around exercise.8 Positive or negative, results at one dose do not prove anything about another. The Australian limit for pharmacist-only (Schedule 3) CBD is 150 mg a day.11 See CBD dosage: what trials used.

What Australian medical bodies say

  • Australian Rheumatology Association. Reported in 2021, its position statement said reviews of cannabinoids for chronic non-cancer pain, including rheumatoid arthritis, “indicate at best modest efficacy with significant adverse effects”.12
  • RACGP. The Royal Australian College of General Practitioners calls the overall evidence for medicinal cannabis “limited and inconclusive” and says it should only be considered after first-line, evidence-based treatments have been exhausted.13
  • TGA. Its guidance says medicinal cannabis should be considered only when registered medicines have been tried, and treatment stopped if benefit is not shown.14

Risks to know about

  • Medicines for inflammatory conditions. CBD blocks several liver enzymes that break down other medicines. Rises in tacrolimus and everolimus levels (drugs that suppress the immune system) have been reported, and raised INR and bleeding have been reported with warfarin and cannabinoids.15 See CBD drug interactions.
  • Liver, especially with paracetamol. In the knee arthritis trial, people taking 600 mg of CBD a day with paracetamol had more liver enzyme rises than those on placebo (15 against 5).7 See CBD and the liver.
  • Delaying proven treatment. Conditions such as rheumatoid arthritis and inflammatory bowel disease have established treatments. An unproven product is not a substitute for them.
  • Creams and balms. Very little CBD passes through the skin into the bloodstream.16 See CBD creams and topicals.

If you are considering it

  • If you have pain, swelling or a diagnosed inflammatory condition, see your GP or specialist about proven treatments first.
  • If you are interested in CBD, ask what human trial evidence supports it for your specific condition, rather than for “inflammation” in general.
  • Tell your doctor and pharmacist about any CBD product, especially if you take medicines that suppress the immune system, blood thinners or regular paracetamol.

See talking to your GP about CBD.

Footnotes

  1. Henshaw FR, Dewsbury LS, Lim CK, Steiner GZ. The effects of cannabinoids on pro- and anti-inflammatory cytokines: a systematic review of in vivo studies. Cannabis and Cannabinoid Research, 2021. https://pubmed.ncbi.nlm.nih.gov/33998900/ ↩

  2. World Health Organization Expert Committee on Drug Dependence. Cannabidiol (CBD) critical review report, 2018. https://cdn.who.int/media/docs/default-source/controlled-substances/whocbdreportmay2018-2.pdf ↩ ↩2

  3. ClinicalTrials.gov. Cannabidiol for Crohn’s disease (NCT01037322), results published by Naftali et al. as “Low-dose cannabidiol is safe but not effective in the treatment for Crohn’s disease, a randomized controlled trial”, Digestive Diseases and Sciences, 2017. https://clinicaltrials.gov/study/NCT01037322 ↩

  4. Kafil TS, Nguyen TM, MacDonald JK, Chande N. Cannabis for the treatment of Crohn’s disease and ulcerative colitis: evidence from Cochrane reviews. Inflammatory Bowel Diseases, 2020. https://pubmed.ncbi.nlm.nih.gov/31613959/ ↩ ↩2

  5. Irving PM, et al. A randomized, double-blind, placebo-controlled, parallel-group, pilot study of cannabidiol-rich botanical extract in the symptomatic treatment of ulcerative colitis. Inflammatory Bowel Diseases, 2018. https://pubmed.ncbi.nlm.nih.gov/29538683/ ↩

  6. Vela J, et al. Cannabidiol treatment in hand osteoarthritis and psoriatic arthritis: a randomized, double-blind, placebo-controlled trial (conference abstract; published in Pain, 2022). https://acrabstracts.org/abstract/cannabidiol-treatment-in-hand-osteoarthritis-and-psoriatic-arthritis-a-randomized-double-blind-placebo-controlled-trial/ ↩ ↩2 ↩3

  7. Pramhas S, et al. Oral cannabidiol as add-on to paracetamol for painful chronic osteoarthritis of the knee. The Lancet Regional Health Europe, 2023. https://pmc.ncbi.nlm.nih.gov/articles/PMC10682664/ ↩ ↩2 ↩3

  8. Crossland BW, et al. Acute supplementation with cannabidiol does not attenuate inflammation or improve measures of performance following strenuous exercise. Healthcare, 2022. https://pmc.ncbi.nlm.nih.gov/articles/PMC9222918/ ↩ ↩2

  9. Isenmann E, et al. Influence of short-term chronic oral cannabidiol application on muscle recovery and performance after an intensive training protocol: a randomized double-blind crossover study. Journal of the International Society of Sports Nutrition, 2024. https://pmc.ncbi.nlm.nih.gov/articles/PMC10997358/ ↩

  10. ClinicalTrials.gov. Cannabidiol for COVID-19 patients with mild to moderate symptoms (CANDIDATE study, NCT04467918). https://clinicaltrials.gov/study/NCT04467918 ↩ ↩2

  11. Therapeutic Goods Administration. Final decision on down-scheduling of low-dose cannabidiol, 2020. https://tga.gov.au/node/284859 ↩

  12. Rheuma.com.au. Can cannabis help with chronic pain and inflammatory diseases? (report of the Australian Rheumatology Association position statement), 19 May 2021. https://www.rheuma.com.au/?p=568 ↩

  13. Royal Australian College of General Practitioners. Position statement: use of medicinal cannabis products in Australia (2019 update). https://www.racgp.org.au/advocacy/position-statements/view-all-position-statements/clinical-and-practice-management/medical-cannabis ↩

  14. Therapeutic Goods Administration. Guidance for the use of medicinal cannabis in Australia: overview. https://www.tga.gov.au/resources/resource/guidance/guidance-use-medicinal-cannabis-australia-overview ↩

  15. Systematic review of drug interactions with cannabidiol and other cannabinoids, 2024. https://pmc.ncbi.nlm.nih.gov/articles/PMC11167383/ ↩

  16. Review of topical and transdermal delivery of cannabidiol, 2024. https://pmc.ncbi.nlm.nih.gov/articles/PMC11172078/ ↩

Common questions

Is CBD anti-inflammatory?

In cells and animals, often yes. A review of animal studies found CBD reduced levels of inflammatory signalling molecules in most of them. In people, trials in inflammatory bowel disease, arthritis and muscle damage after exercise have mostly found CBD no better than placebo, so there is no good evidence that it reduces inflammation in a way that matters to your health.

Does CBD help inflammatory bowel disease?

Small trials say no or are inconclusive. A low-dose CBD trial in Crohn's disease found it safe but not effective, and in ulcerative colitis remission rates were 24% with a CBD-rich cannabis extract (which also contained some THC) and 26% with placebo. A review of the Cochrane evidence said no firm conclusions can be made.

Does CBD reduce inflammation after exercise?

Not in the trials so far. In 24 female athletes, three doses of CBD taken around a hard leg workout did not reduce inflammation, muscle damage or fatigue compared with placebo. A study of 17 trained athletes taking 60 mg after training sessions found no clear effects either.

Why do lab results not always apply to people?

In a dish, cells can be bathed in CBD directly, and animals can be given large doses by injection. In people, only about 6% of a swallowed dose reaches the blood when taken without food. Most treatments that work in cells or mice fail when tested in people, which is why human trials matter.

This page is general information, not medical or legal advice. Laws and evidence change; we show the date we last checked the facts at the top of every page. Talk to your doctor or pharmacist before starting, stopping or changing any medicine.

Didn't find what you needed? Ask us a question.

Keep reading