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.
Below: 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 148mg 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.
Not sure it’s migraine? See tension headaches.
FAQs
Does magnesium help with migraines?
It may help prevent them for some people. Reviews of trials found fewer attacks per month, though many trials were small.
How much magnesium should I take for migraines?
Trials used 400 to 600mg a day. The NHS says 400mg or less from supplements is unlikely to cause harm, so ask your GP before taking more.
What is the best magnesium for migraines?
No form is proven best. Citrate and glycinate are well absorbed; oxide is cheaper but poorly absorbed and more likely to cause diarrhoea.
How long does magnesium take to work for migraines?
Trials ran for about 12 weeks. Keep a headache diary and give it around three months.
Can magnesium stop a migraine once it starts?
Not as a supplement. Intravenous magnesium is sometimes used in hospital, but tablets are for prevention.
Is magnesium or riboflavin better for migraines?
NICE mentions riboflavin 400mg a day. Magnesium also has trial evidence. Some people try one, then the other, with their GP’s advice.
Sources
- 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.
