CBD LoveThe independent Australian guideSearch

Can you take CBD with antidepressants?

Not without medical advice. CBD blocks liver enzymes that process many medicines, and one small study found it raised citalopram blood levels.

Facts checked 13 November 20263 min readHow we research

Not without checking with your doctor or pharmacist. CBD blocks several of the liver enzymes that break down medicines, so it can change the blood levels of other drugs.1 For antidepressants, the human evidence is one small study, which found that CBD raised blood levels of citalopram.2

Why might CBD interact with an antidepressant?

The liver clears many medicines using a family of enzymes. CBD inhibits several of them, including the ones known as CYP2C19, CYP3A4 and CYP2C9.1 When an enzyme is blocked, a medicine that depends on it can build up in the blood.

The effect can be large for some drugs. CBD raises the active breakdown product of the epilepsy medicine clobazam about 3-fold, and it roughly doubled blood exposure to caffeine in one study.1

What is known about antidepressants specifically?

Less than you might expect. The human evidence is one small Australian study. Six young people with anxiety disorders, who were on stable treatment with citalopram or escitalopram, had CBD added at 200 to 800 mg a day for 12 weeks. Their citalopram blood levels rose significantly. The researchers could not tell whether this caused more antidepressant side effects.2

In laboratory tests in the same study, CBD had only minimal effects on the breakdown of sertraline, fluoxetine and mirtazapine.2 Laboratory results do not always carry over to people, and we found no verified human studies of CBD with other antidepressants.

The absence of data is not reassurance. The United Kingdom’s food regulator has set a provisional upper limit of 10 mg of CBD a day for a healthy adult, and advises people on prescription medication to avoid CBD foods without the advice of a medical professional.3

What else should you consider?

  • Sleepiness can add up. CBD causes drowsiness in some people, and the effect adds to that of other sedating medicines and alcohol.1
  • Low doses are not cleared. The best-documented interactions come from prescription-strength doses, but low doses have not been shown to be free of them.13
  • Other medicines count too. A systematic review rated warfarin, valproate, tacrolimus and sirolimus as the most widely reported and potentially highest-risk interactions with cannabinoids.4

Does CBD treat depression?

There is not enough evidence to say. We found no completed placebo-controlled trial of CBD for major depression.5 In an arthritis trial, 20 to 30 mg of CBD a day had no effect on depression scores.6 The Royal Australian and New Zealand College of Psychiatrists says there is insufficient evidence to support medicinal cannabis for mental disorders.7

What should you do?

  • Tell your prescriber and pharmacist about everything you take, including CBD.
  • Do not stop or reduce an antidepressant in order to try CBD. That is a decision to make with your doctor.
  • If you start CBD on prescription, report new drowsiness, dizziness or a change in mood.

A prescriber decides whether CBD is appropriate alongside your other medicines.

Read the full guide: CBD drug interactions and CBD for depression.

Footnotes

  1. Epidiolex (cannabidiol) prescribing information, United States. https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=8bf27097-4870-43fb-94f0-f3d0871d1eec ↩ ↩2 ↩3 ↩4 ↩5

  2. Anderson LL and others. Citalopram and cannabidiol: in vitro and in vivo evidence of pharmacokinetic interactions relevant to the treatment of anxiety disorders in young people. Journal of Clinical Psychopharmacology, 2021. https://doi.org/10.1097/JCP.0000000000001427 ↩ ↩2 ↩3

  3. UK Food Standards Agency. Provisional cannabidiol (CBD) acceptable daily intake: lay summary. https://www.gov.uk/government/publications/provisional-cannabidiol-cbd-acceptable-daily-intake-adi/lay-summary ↩ ↩2

  4. Systematic review of cannabinoid drug interactions. https://pmc.ncbi.nlm.nih.gov/articles/PMC11167383/ ↩

  5. ClinicalTrials.gov. Registered trial of CBD oil for treatment-resistant depression, not yet reported. https://clinicaltrials.gov/study/NCT07696871 ↩

  6. Vela J and others. Cannabidiol treatment in hand osteoarthritis and psoriatic arthritis: a randomized, double-blind, placebo-controlled trial. https://acrabstracts.org/abstract/cannabidiol-treatment-in-hand-osteoarthritis-and-psoriatic-arthritis-a-randomized-double-blind-placebo-controlled-trial/ ↩

  7. Royal Australian and New Zealand College of Psychiatrists. Updated clinical memorandum: therapeutic use of medicinal cannabis, March 2024. https://ranzcp.org/news-analysis/updated-clinical-memorandum-therapeutic-use-of-medicinal-cannabis ↩

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