CBD, Headaches and Migraine: Evidence and Safety

Is there a clinical trial of CBD for migraine?

Yes. The trial most people mean is Schuster and colleagues, published in Headache in December 2025 (opens in a new tab). The team at the University of California, San Diego enrolled 92 adults with migraine. Each person treated up to four separate attacks, at least a week apart, with one of four vaporised cannabis flowers in random order:

• about 6 % THC (THC-dominant)
• about 11 % CBD (CBD-dominant, with 0.35 % THC)
• 6 % THC plus 11 % CBD
• placebo flower

The main outcome was pain relief two hours after vaping. The THC plus CBD flower beat placebo on that outcome (67 % vs 47 % of treated attacks), and also on being fully pain-free at two hours (35 % vs 16 %). The THC-dominant flower beat placebo for pain relief, though not for being pain-free.

The CBD-dominant flower did better than placebo at one hour, a secondary time point: pain relief in 59 % vs 37 % of attacks, and freedom from the most bothersome symptom in 41 % vs 22 %. It was not superior to placebo on being pain-free at one hour, or on the two-hour outcomes.

The authors note that they tested one strength of each cannabinoid and one THC to CBD ratio, that some participants had used cannabis before, and that the flower came from a US government research supply. A systematic review of randomised trials published in September 2026 (opens in a new tab) rated the evidence for vaporised THC plus CBD in acute migraine as moderate certainty. For the CBD-dominant formulation, it did not find a clear benefit.

A Brazilian trial (CAMTREA) compared placebo drops with daily oral drops containing up to 133 mg CBD, 66 mg CBG and 4 mg THC, given alongside usual preventive treatment in chronic migraine. Its registry entry (opens in a new tab) says recruitment was stopped with 75 patients enrolled and the study ended in February 2025. We could not find published results as of October 2026.

A placebo-controlled trial of a CBD-dominant capsule is under way at the University of Calgary chronic migraine trial (NCT03972124) (opens in a new tab). It compares a high-CBD, low-THC capsule at 100 mg or 200 mg a day (opens in a new tab) with placebo in adults whose chronic migraine has not responded to at least two preventive medicines. It started recruiting in April 2026, with completion planned for December 2028.

CBD and headaches: CBD alone or THC plus CBD?

Most cannabis and headache research is about cannabis, not CBD. Whether a study used CBD alone is what tells you if it applies to a CBD supplement.

The largest dataset comes from the Strainprint app study by Cuttler and colleagues (2020) (opens in a new tab). People logged headache ratings before and after inhaling cannabis across 12,293 headache sessions and 7,441 migraine sessions, and their ratings dropped by roughly half. The study had no placebo group, and the CBD content of the product made no measurable difference to the ratings. Users also took larger doses over time, which the authors read as a sign of tolerance.

A 2025 review of cannabinoids in headache in Current Opinion in Neurology (opens in a new tab) describes the positive reports so far as mostly retrospective. It lists what is still open: standardised dosing, long-term safety data, and questions about dependence and medication-overuse headache.

If you want to understand what "full-spectrum" or "THC-free" means on a label, see our guide to full-spectrum, broad-spectrum and isolate CBD.

What the animal studies tested

Two mouse studies come up often:

• Sturaro and colleagues (Pain, 2023) (opens in a new tab) injected mice with CGRP, a protein involved in migraine, to trigger migraine-like behaviour, then gave CBD by injection. CBD reduced facial sensitivity in both sexes and signs of spontaneous pain in females, and did not change light sensitivity in females. The authors conclude that CBD prevented migraine-like states in these mice.
• Zorrilla and colleagues (Cephalalgia, 2025) (opens in a new tab) tested CBD alone, THC alone and several combinations in three mouse models. A 100:1 CBD to THC mix reduced light aversion, which CBD alone did not. None of the treatments changed touch sensitivity around the eye.

Zorrilla's team gave CBD at 100 mg per kg of body weight on its own, and at 1 to 100 mg per kg combined with THC at 1 mg per kg. Mouse studies are an early step. The Calgary trial above is testing a CBD-dominant capsule in people.

What about tension-type and cluster headaches?

Research on these headache types is at an earlier stage. We did not find a controlled human trial of CBD for tension-type or cluster headache as of October 2026.

For cluster headache, a 2014 retrospective report from a Tel Aviv headache clinic (opens in a new tab) followed 18 patients with treatment-resistant chronic cluster headache who used medical cannabis, mostly smoked. Fifteen of them reported that their headache severity fell by more than half. The report had no control group.

If your headaches feel like pressure or a tight band on both sides of your head, the NHS page on tension headaches (opens in a new tab) explains what a GP will usually ask and when to see one.

What migraine organisations say about CBD

The American Migraine Foundation (2018) (opens in a new tab) said CBD had not yet been formally studied for migraine. It warned about unregulated products that might contain THC, and advised talking to your doctor first because "these drugs do interact with the body". That page predates the 2025 trial.

For any supplement, the UK's Migraine Trust non-drug treatments factsheet (opens in a new tab) (reviewed February 2025) says to check with your GP, pharmacist or specialist first, because they can check for interactions.

Can CBD give you a headache?

It can be a side effect. In a 2018 placebo-controlled safety trial in healthy adults (opens in a new tab), headache was among the most common adverse events. In the multiple-dose part, which used 750 mg or 1,500 mg twice a day, 8 of 18 people taking CBD reported headache, against none of the 6 on placebo.

We did not find any study that looked specifically at a "CBD hangover" or headache the next morning. Our article on headache and other reported CBD side effects covers what is known, including the liver findings and who should avoid CBD.

Cannabis and medication-overuse headache

The NHS page on tension headaches (opens in a new tab) says that taking painkillers for headaches too often or for a long time can also cause headaches.

A 2021 Stanford chart review (opens in a new tab) of 368 people with chronic migraine found medication-overuse headache in 81 % of current cannabis users, against 41 % of non-users. Cannabis use was also linked with opioid use. This kind of study shows an association, not cause and effect, and "cannabis" in the charts covered a range of products. It is still a reason to tell your doctor about any cannabis or CBD use if you get frequent headaches.

Can you take CBD with triptans or other migraine medicines?

Ask a pharmacist before you combine them.

• EFSA (February 2026) (opens in a new tab) concluded that the safety of CBD as a food cannot be established for people taking medication.
• The UK Food Standards Agency (opens in a new tab) does not recommend CBD for people taking any medication unless under medical direction.
• The EU product information for Epidyolex (opens in a new tab), a prescription CBD medicine, says CBD inhibits the liver enzyme CYP2C19 in lab studies and may raise blood levels of medicines broken down by it. The same document reports that CBD did not affect the enzyme CYP3A4 in a human study with midazolam.
• Some migraine medicines do depend on CYP3A4. The eletriptan (Relpax) product information (opens in a new tab), for example, says it should not be taken with potent CYP3A4 inhibitors. CBD has not been shown to be a potent CYP3A4 inhibitor, but no study has tested it with eletriptan.

We did not find any published study testing CBD together with a triptan, a gepant or a CGRP antibody. Interaction data for CBD also come from prescription doses, not supplement doses. Bring the full list of what you take, including preventives such as topiramate or amitriptyline, painkillers and anti-sickness tablets, to your pharmacist. Our guide to CBD and medicine interactions explains which drug groups need the most caution.

Legal status and product quality

The trial products above were vaporised cannabis flower containing THC. In the EU, the European Commission treats CBD as a novel food, and in February 2026 EFSA (opens in a new tab) said it would assess each CBD novel food application on the data its applicant provides. Our overview of CBD rules across Europe covers the country details.

When you read about a CBD study, check whether it involved THC, how the product was taken, the dose, and whether there was a placebo group. Our guide on how to read CBD health claims walks through those checks.

When a headache needs urgent care

Most headaches are not serious. The NHS (opens in a new tab) says to call 999 (or your local emergency number) or go to A&E if you have a headache and:

• it started suddenly and is extremely painful
• you have had a seizure, or numbness or weakness in the body or face
• you have had a head injury in the last 3 months
• you are finding it hard to speak, balance, walk or remember things
• you are drowsy or confused, or have lost vision
• you have a rash that does not fade under a glass, a very high temperature, a stiff neck, or bright lights bother you

The NHS also advises an urgent GP appointment for a headache with vision problems, vomiting, jaw pain when eating, or one triggered by coughing, sneezing or bending down. See a GP if you get headaches regularly or they are getting worse.

What to bring to your doctor

If you are thinking about CBD and you live with migraine or frequent headaches, these make the conversation more useful:

• a headache diary: how often, how long, how bad, and what else happened (the NHS links to The Migraine Trust's diary guidance (opens in a new tab))
• every medicine and supplement you take, with doses
• how many days a month you take painkillers or triptans
• any cannabis or CBD use, including the product and its THC content
• pregnancy, breastfeeding or plans to conceive

FAQ