By Marcello Cherchi, MD PhD
For patients
Taking extra magnesium by mouth may make you have less migraines. If you take too much magnesium, you may get diarrhea. You should not take magnesium if you are pregnant.
For clinicians
Overview
In otoneurology, oral magnesium oxide may be effective in prophylaxis against migraine. It is sometimes used as adjunctive therapy in the sense that it may potentiate migraine prophylaxis medications, or enable those medications to be used at lower doses. High doses of magnesium may cause diarrhea. Magnesium supplementation should not be taken during pregnancy due to possible effects on fetal bone metabolism.
Introduction
There are various magnesium formulations used in medicine (such as magnesium oxide, magnesium citrate, magnesium sulfate, magnesium chloride, magnesium lactate, magnesium malate), the most common of which include magnesium oxide and magnesium citrate.
Pharmacology
Magnesium ions play a role in neural transmission (Dolati et al. 2020).
Adverse effects
Magnesium can accelerate gut motility. Some patients experience diarrhea when taking high doses of magnesium.
Cautions and contraindications
Magnesium is currently not recommended during pregnancy because of possible effects on the bone metabolism of the fetus (Matsuda et al. 1997; Nassar et al. 2006; Wedig et al. 2006; Yokoyama et al. 2010).
Relevance in otoneurology
Magnesium (usually magnesium oxide) has been studied in the prophylaxis of migraine (Chiu et al. 2016), though its mechanism of action remains unclear (Domitrz and Cegielska 2022). Meta-analyses of trials generally conclude that magnesium is “possibly effective” (Marmura et al. 2015; von Luckner and Riederer 2018) for this purpose. The efficacy of magnesium becomes apparent within 9 – 12 weeks in adults (Peikert et al. 1996) and within 16 weeks in children (Wang et al. 2003). The doses of magnesium studied were 300 – 600 mg once per day.
In some instances magnesium appears to potentiate the effect of migraine prophylaxis medications, or enable those medications to be used at lower doses (Khani et al. 2021).
Other notes
Magnesium supplements are available over-the-counter.
References
Chiu HY, Yeh TH, Huang YC, Chen PY (2016) Effects of Intravenous and Oral Magnesium on Reducing Migraine: A Meta-analysis of Randomized Controlled Trials. Pain Physician 19: E97-112.
Dolati S, Rikhtegar R, Mehdizadeh A, Yousefi M (2020) The Role of Magnesium in Pathophysiology and Migraine Treatment. Biol Trace Elem Res 196: 375-383. doi: 10.1007/s12011-019-01931-z
Domitrz I, Cegielska J (2022) Magnesium as an Important Factor in the Pathogenesis and Treatment of Migraine-From Theory to Practice. Nutrients 14. doi: 10.3390/nu14051089
Khani S, Hejazi SA, Yaghoubi M, Sharifipour E (2021) Comparative study of magnesium, sodium valproate, and concurrent magnesium-sodium valproate therapy in the prevention of migraine headaches: a randomized controlled double-blind trial. J Headache Pain 22: 21. doi: 10.1186/s10194-021-01234-6
Marmura MJ, Silberstein SD, Schwedt TJ (2015) The acute treatment of migraine in adults: the american headache society evidence assessment of migraine pharmacotherapies. Headache 55: 3-20. doi: 10.1111/head.12499
Matsuda Y, Maeda Y, Ito M, Sakamoto H, Masaoka N, Takada M, Sato K (1997) Effect of magnesium sulfate treatment on neonatal bone abnormalities. Gynecol Obstet Invest 44: 82-8. doi: 10.1159/000291492
Nassar AH, Sakhel K, Maarouf H, Naassan GR, Usta IM (2006) Adverse maternal and neonatal outcome of prolonged course of magnesium sulfate tocolysis. Acta Obstet Gynecol Scand 85: 1099-103. doi: 10.1080/00016340600756896
Peikert A, Wilimzig C, Kohne-Volland R (1996) Prophylaxis of migraine with oral magnesium: results from a prospective, multi-center, placebo-controlled and double-blind randomized study. Cephalalgia 16: 257-63.
von Luckner A, Riederer F (2018) Magnesium in Migraine Prophylaxis-Is There an Evidence-Based Rationale? A Systematic Review. Headache 58: 199-209. doi: 10.1111/head.13217
Wang F, Van Den Eeden SK, Ackerson LM, Salk SE, Reince RH, Elin RJ (2003) Oral magnesium oxide prophylaxis of frequent migrainous headache in children: a randomized, double-blind, placebo-controlled trial. Headache 43: 601-10.
Wedig KE, Kogan J, Schorry EK, Whitsett JA (2006) Skeletal demineralization and fractures caused by fetal magnesium toxicity. J Perinatol 26: 371-4. doi: 10.1038/sj.jp.7211508
Yokoyama K, Takahashi N, Yada Y, Koike Y, Kawamata R, Uehara R, Kono Y, Honma Y, Momoi MY (2010) Prolonged maternal magnesium administration and bone metabolism in neonates. Early Hum Dev 86: 187-91. doi: 10.1016/j.earlhumdev.2010.02.007
