Migraine and Magnesium

Timothy C. Hain, MD Page last modified: March 3, 2019 See also -- many pages on migraine on this site

Main points:

Migraines are an immensely common human problem, affecting about 15% of the entire population (mainly women). A little known aspect of migraine is that they are more likely when magnesium blood levels are low, and some migraines can be aborted by large amounts of magnesium, usually given in the emergency room (Sun-edelstein et al, 2009).

The evidence for prophylaxis of migraine by magnesium in adults is reasonable, but the evidence for use in children as well as an abortive is weak. Still, magnesium is probably very safe, and for this reason it is often recommended for children.

How magnesium is regulated:

Magnesium in the blood reflects a balance between absorption in the gut and elimination through the kidney. Magnesium absorption is reduced by some stomach medications for reflux, called proton pump inhibitors. Some of them are over the counter -- e.g. prilosec. This means that it is especially important to take magnesium supplements for migraine prevention, if you take a PPI. Magnesium is regulated through the kidney, where it is reabsorbed. Incomplete reabsorption causes magnesium wasting (Viering et al, 2017).

There are about a dozen genes that result in hypmagnesiumia - but these are extremely rare in clinical medicine, and finding them does not contribute to therapy (Viering et al, 2017).

Evidence for magnesium supplements as prophylaxis:

Evidence for magnesium working as a migraine abortive:

Proton pump inhibitors (PPI) and magnesium.

Proton pump inhibitors approved in the US include:

  1. omeprazole (Prilosec),
  2. lansoprazole (Prevacid),
  3. rabeprazole (Aciphex),
  4. pantoprazole (Protonix),
  5. esomeprazole (Nexium), and
  6. Zegarid, a rapid release form of omeprazole.

Recent papers showing an association between PPI use and low magnesium include:

One would think that use of PPI would be correlated with more migraines. This does appear to be true in large studies (e.g. Liang et al, 2014). H2 blockers, such as Ranitidine ("Zantac"), might be less likely to cause headache. So far, there has not been a comparison trial (between PPI and H2 blockers).

Which types of magnesium works best for migraine ?

The goal for magnesium supplements is to have an intake of somewhere between 400 and 600 mg of magnesium/day. Magnesium is a metal, and to be in solution it has to be combined with sometime else - generally a weak organic acid- this might be citrate, malate, oxide, gluconate, glycinate, sulfate, taurate, threonate, etc. Most of these are "just along for the ride". Once the pill dissolves in your stomach, you get the mangesium ion, and whatever it was bound to (e.g. citrate - -citric acid). Magnesium tends to irritate the bowel and for this reason is used as a laxative. It is usually a good idea to combine it with something bland, like calcium. This is the reason why there are many "cal-mag" preparations.

It is doubtful that much magnesium can be absorbed through the skin -- i.e. with lotions, sprays or epson salts. These are probably placebos.

Although magnesium can be given intravenously in very large amounts, it is doubtful that it stays in the body very long, as the kidneys keep the magnesium level regulated. (Swaminathan, 2003)

Concerning the best form of oral magnesium, Swaminathan (2003) states that magnesium gluconate is the best choice, preferably given in divided doses to avoid diarrhea. In our patients, patients often choose to take Cal-Mag, which has calcium included in the tablet, which seems to make it less irritating to the bowel. Magnesium oxide may be slower to be absorbed (perhaps this is good). There doesn't seem to be any science at all about which product works best for migraine. von Luckner and Riederer suggested that Magnesium dicitrate, 600 mg, was the optimum preparation.

The most common preparations are:

Slow-Mag tablets contain 135 mg of Magnesium. These are coated so they dissolve slowly. We do not have anyone taking these. One would think about 4/day would be needed.

One of our patients likes the "Smarty-Pants" gummy magnesium. This product contains quite a bit of other stuff, and it is not a "pure" magnesium product. This adds risk of side effects. It also has 3 grams of sugar, and presumably is not so good for your teeth either.

One would think that one of the many 500 mg magnesium gluconate preparations might work better, if you can find one.

 

Recommendations:

Overall, we agree with the conclusion of Pardutz et al (2012) : "The data available suggest that magnesium has a potential role in the prophylaxis, but the results in acute therapy are far less convincing."

We suggest that most patients with migraine should be taking magnesium 400-600 mg/day.

The main issue that we have encountered with Magnesium intake is indigestion. Preparations with calcium seem to make this less likely.

 

References: