Children's migraines cut further by adding weekly vitamin D to topiramate (500,000 IU ?) - RCT
Efficacy of Topiramate Alone and Topiramate Plus Vitamin D3 in the Prophylaxis of Pediatric Migraine: A Randomized Clinical Trial
Iranian Journal of Child Neurology, Autumn 2020; 14(4): 77–86, https://doi.org/10.22037/ijcn.v15i1.18017
Razieh Fallah, Saeedreza Sarraf Yazd, Seid Mojtaba Sohrevardi
Summary by Claude Opus 5.5 - November, 2026
Children with migraine had fewer attacks when vitamin D3 was added to topiramate, the usual preventive drug: about 6 attacks a month vs 10 with topiramate alone, after two months.
This was a small randomized trial in Yazd, Iran. 60 children aged 5–15 enrolled and 57 finished (28 on topiramate alone, 29 on topiramate plus vitamin D). All had 25(OH)D above 30 ng/mL at the start, so none were deficient. Both groups took topiramate 2 mg/kg/day for 60 days. The vitamin D group also took "one 500,000 IU vitamin D3 pearl weekly." There was no separate loading dose and no placebo, and 25(OH)D was not reported after treatment.
The 500,000 IU dose is almost certainly a misprint for 50,000 IU (about 7,000 IU a day). Iran's standard high-dose pearl is 50,000 IU, and no 500,000 IU capsule appears to be sold anywhere Iranian vitamin D forms. The trial registry repeats the same number IRCT registry.
Results after treatment, vitamin D group vs topiramate alone:
- Monthly migraine attacks: 6.1 vs 9.9 (P=0.01)
- Disability score (PedMIDAS): 19.2 vs 22.1 (reported P=0.02)
- Attacks cut by more than half: 75.9% vs 60.7% (reported P=0.01)
- Severity and length of attacks: no difference
- Side effects: mild and short-lived, 17% vs 14%
What this does NOT show / limitations
- Open-label with no placebo; only the staff measuring outcomes were blinded
- Small, one center, only 2 months, with no follow-up after stopping
- The vitamin D blood level reached is unknown
- Reporting errors: recalculated from the paper's own numbers, the "cut by more than half" difference (17/28 vs 22/29) gives P≈0.2 and the disability difference P≈0.14, so neither is significant. Only the drop in attack frequency holds up.
- Attacks were compared after only 8 weeks, with no loading dose. If the dose was 50,000 IU weekly, blood levels were probably still rising (this takes about 3 months), so any benefit may be underestimated.
- The children were not deficient, so results may differ in deficient children
Study was cited 25 times in Google Scholar as of Nov 2026
Related in VitaminDWiki
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- Headache
- Vitamin D and Migraine
- Migraine in children reduced with vitamin D supplementation – April 2014
Headaches
- Children's migraine attacks cut 56% by topiramate plus vitamin D – ranked 2nd of 22 preventives - meta-analysis
- Migraine Headache duration and intensity reduced by 50,000 IU vitamin D every two week plus probiotics – RCT
- Migraine headache 5X less likely if optimal level of vitamin D
- Migraine Headache association with poor gut
- Half as many headaches if high Vitamin D level (age 6-19)
- Magnesium and Migraines - many studies
- Cluster and Migraine headache treatment protocol
- Cluster Headaches treated by high-dose Vitamin D, etc. (interview and transcript)
- Migraines in youths with low Vitamin D wonderfully treated by Vitamin D
- Migraine headache 5X less likely if optimal level of vitamin D
Large Doses of Vitamin D
- 300,000 IU of Vitamin D - many studies
- 400,000 IU of vitamin D 3 days after COVID symptoms reduced 14 day mortality by 3X – Annweiler RCT
- Critically ill children – randomized clinical trial to give single doses of up to 400,000 IU of vitamin D – 2019
- 400,000 IU of vitamin D reduced adult pain and improved quality of life
- Tuberculosis recovery speeded up by single 450,000 IU dose of vitamin D – RCT
- Vitamin D3 loading dose of 500,000 IU for elderly
- 600,000 IU of vitamin D2 every 4 months for decades in East Germany – 1987
Note:
- VitaminDWiki had 400,000 capsules of vitamin D and placebos made for use in an adult COVID trial in 2020, but trial was cancelled