Last updated: October 2026
Magnesium may help prevent migraines for some people. A 2025 review of supplement trials found magnesium cut migraine attacks by about 2.5 a month compared with control groups, though many trials were small. The doses used, often 600mg a day, are above the NHS’s 400mg supplement guide, so talk to your GP or pharmacist before taking that much.
iBelow: what the trials found, which form and dose were used, side effects, how magnesium compares with other options NICE mentions, and when to see a doctor.
Does magnesium help migraines? The research
| Study | What it found |
|---|---|
| German trial, 1996 (81 people, 12 weeks) | 600mg a day cut attack frequency by 42%, against 16% on placebo. 19% had diarrhoea |
| Review, 2016 (10 oral trials, 789 people) | Oral magnesium reduced how often and how badly migraines struck |
| Review, 2025 (22 supplement trials) | Magnesium reduced attacks by about 2.5 a month and migraine days by about 1.7 a month versus control |
| Hospital use | Intravenous magnesium is sometimes used for severe attacks in hospital; this is different from supplements |
The evidence is encouraging but not strong: many trials were small, and some were negative. Magnesium is used for prevention over weeks, not for stopping an attack once it starts.
Dose and form used in trials
- Dose: most prevention trials used about 400 to 600mg of magnesium a day.
- Form: trials used citrate, oxide and others. No form has been proven best for migraine; citrate and glycinate are better absorbed than oxide. See types of magnesium.
- NHS guide: 400mg a day or less from supplements is unlikely to cause harm. Higher doses should only be taken on medical advice.
Magnesium contributes to normal functioning of the nervous system and the reduction of tiredness and fatigue. Our Magnesium Glycinate Sleep Complex gives 290mg per serving as an evening drink. It isn’t designed or dosed as a migraine treatment.
How long it takes and how to take it
- Give it 3 months of daily use before judging, as trials did.
- Keep a headache diary of attacks per month before and during, so you can see if it’s working.
- Split the dose with meals if it upsets your stomach.
- Separate it from some medicines by a few hours. See best time to take magnesium.
Side effects and who should check first
- Diarrhoea is the most common side effect, especially at higher doses.
- Kidney disease: don’t take magnesium supplements without medical advice.
- Medicines: magnesium reduces absorption of some antibiotics and osteoporosis medicines.
- Pregnancy: speak to your midwife or GP before taking any supplement for migraine. See magnesium in pregnancy.
Magnesium vs other migraine options
| Option | Status in the UK |
|---|---|
| Riboflavin (vitamin B2) 400mg | NICE says it may reduce migraine frequency and intensity for some people |
| Magnesium | Some trial evidence; not specifically in NICE’s guideline |
| Coenzyme Q10 | Some trial evidence |
| Prescription preventers | NICE recommends discussing propranolol, topiramate or amitriptyline |
| CBD | No good CBD-only trials. See CBD for migraines |
Lifestyle factors matter too: regular sleep and meals, enough water, and spotting your triggers. See caffeine and how it affects you.
When to see a GP
See a GP if you get headaches several times a week, if painkillers aren’t working or you’re using them on more than 10 days a month, or if your headaches are changing. Call 999 or go to A&E for a sudden, severe headache, or one with weakness, confusion, slurred speech, a stiff neck and fever, or after a head injury.
Related guides
- Not sure it’s migraine? See tension headaches.
- Magnesium glycinate side effects and dose.
- Waking up with a headache: causes and what to do.
- Not sure it’s a migraine? Our guide to a headache behind the eyes compares migraine, tension, sinus and cluster headaches.
- Riboflavin (vitamin B2) and the other B vitamins explained.
- Migraine symptoms, triggers and NICE treatment options.
- If your migraines come with dizziness or spinning, see vertigo and vestibular migraine.
- If you have seen magnesium taurate suggested for migraines, our guide to what magnesium taurate is explains what the research does and doesn’t show.
- For the differences between the main forms, see magnesium glycinate vs citrate vs threonate.
- Migraine studies often use higher doses, so check whether you can have too much magnesium and speak to your GP first.
- Not sure your headache is a migraine? Our headache location guide compares the common types by where they hurt.
Sources 5
- Peikert A et al. Prophylaxis of migraine with oral magnesium: a placebo-controlled randomized study. Cephalalgia, 1996.
- Chiu HY et al. Effects of intravenous and oral magnesium on reducing migraine: a meta-analysis. Pain Physician, 2016.
- Talandashti MK et al. Effects of selected dietary supplements on migraine prophylaxis: a systematic review and dose-response meta-analysis. Neurol Sci, 2025.
- NICE. Headaches in over 12s: diagnosis and management (CG150).
- NHS. Vitamins and minerals: magnesium.
