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Ultra Pure Topical Magnesium

Allergic to Magnesium?

I recently had a phone call with someone who told me that they were allergic to sea water.

At first, I admit, I was a bit skeptical – but then I realized, why should I be…our bodies being the strange, yet wonderfully complex, biological systems that they are. So, I sat back to listen to the background on this completely new topic for me, and it really had me wondering. If someone can be allergic to sea water – which contains high amounts of magnesium chloride, on top of the more well known sodium chloride – how would that affect them in terms of transdermal magnesium use?

As with most of these conversations, I was instantly crawling all over the internet seeking answers and details on how this could relate to magnesium chloride use, and finding some very interesting information to share.

So here is the question that I know is on your mind now – Can you be allergic to topical magnesium chloride?

The answer? Yes. Yes you can. But then again, you can be allergic to just about anything these days – even water!

To go further into the “hows” and “whys” of this, I’ll start by saying that a true magnesium allergy is extremely rare. After all, our bodies need magnesium to function. Not want, or like, or prefer – need. They require it like a car engine requires oil – no ifs, ands or buts about it. However, as our population becomes exposed to more and more toxins in our environment, less diversity in our food system, more antibiotics and gut-flora-disrupting pharmaceuticals, etc.,  we’re seeing a significant rise in corresponding health issues such as Auto-Immune Diseases and Multiple Chemical Sensitivity.

From what I’ve found, hypersensitivity to magnesium is relatively new in the grand scheme of things and wasn’t actually documented in medical journals until 1990. At this time, two pregnant women were treated with  a prepared solution of intravenous magnesium sulfate (MgSO4) to try and stave off premature labor. Both of these women developed an urticarial rash (hives) within a short period of time, which disappeared once the MgSO4 was discontinued. Although, to be clear, it was never deciphered whether it was indeed the MgSO4 that was the culprit as opposed to the dextrose, sulphur, leaching of chemicals from the plastic bag, or other contaminant in the IV preparation. Additionally, despite the fact that this occurrence was documented 22 years ago, clinical documentation of magnesium hypersensitivity remains difficult to find.

Why? Because a magnesium allergy is completely contradictory to everything that magnesium stands for – in fact, it’s biologically absurd.  In a healthy human body, magnesium is a natural anti-inflammatory; it’s key in histamine metabolism and naturally reduces histamine production. Are you seeing the irony yet?

hypersensitivity to magnesiumWith a magnesium allergy, your body reacts to magnesium exposure as though it is battling a pathogen, resulting in the release of immunoglobulin E (igE) antibodies, histamine and other chemicals. This inflammatory response can manifest as a rash* (moderate – severe) or urticaria, difficulty breathing, rhinitis, dizziness, swelling of the limbs or throat, etc.. Although an extreme magnesium allergy may require you to carry epinephrine and wear a medical alert bracelet, the average allergic reaction should subside with the administration of a mild antihistamine.

*Please do not mistake the common itching sensation or slight redness from transdermal magnesium use for an allergic reaction. There is a vast difference between hypersensitivity to magnesium that causes hives and the normal itching sting of magnesium salts on your skin.


Also, keep in mind that magnesium is necessary in the body for proper detoxification, therefore, may cause detoxification symptoms with its use. Detoxification symptoms include headache, fatigue, brain fog, body ache, and other similar ailments.

So, now that we know that this phenomenon exists, allow me to touch on some additional information…

Why haven’t I heard about this before now?

As I mentioned above, magnesium hypersensitivity is not just rare, but also appears to be a rather new and poorly documented affliction. Most of the information that you’ll find on this subject will be of the anecdotal variety, surfacing mainly in forum discussions, blog posts, and social media commentary. Alongside those, you may run into the occasional vague mentions in clinical studies & medical journals. In fact, this information is so very elusive, I’d almost call it Bigfoot if I didn’t know it to actually exist.

Is it possible to circumvent an allergy to magnesium?

To a certain extent, it may be possible to still supplement with magnesium despite a sensitivity. Many of the allergic responses to magnesium seem to be a result of simply getting too much magnesium at once. In essence, it’s your body’s way of saying “Whoa, slow down!”. I would liken it to feeding someone suffering from starvation – despite the fact that the body needs food to survive, pushing too much and/or the wrong types of food onto a sensitive digestive system can be extremely harmful and even fatal. The same consideration should be made when dealing with a sensitivity to magnesium.

Using smaller, more mild dosages, trying different types of compounds, and building up your internal magnesium stores slowly, are all things to consider if you are dealing with a mild allergic reaction to magnesium.

In terms of our Ancient Minerals line specifically, try diluting the magnesium further than what is suggested in the instructions – for the magnesium oil, you could try a dilution of 25/75 rather than the 50/50 that we suggest in the application guide. If that is still too strong, you can try diluting it further or simply stick to an application such our bath flakes.

If you are in the small group of people that are extremely allergic, however, use of magnesium even in small amounts would not be recommended (obviously).

If I’m allergic to one magnesium compound, does that mean that I’m allergic to all of them?

No, it’s very possible that you could simply be allergic to that specific compound. There are over 20 different forms of magnesium available as supplements – depending on your reaction, you could try switching to a different form. However, please consult with your physician should you decide to explore that route.

If I’m allergic to magnesium supplements, does that mean that I’m allergic to foods containing it as well?

No. The oddest aspect of hypersensitivity to magnesium is that, unlike normal allergies, it usually* does not include magnesium-rich foods. For this reason, those who have found themselves highly allergic to magnesium supplements are usually sent to a dietician to help them plan out meals geared specifically towards meeting their magnesium needs.

*I say “usually” because I have not found evidence that supports a complete negation on this, but neither have I found any to support a response to the positive.

If you have any questions or comments on this topic, feel free to call 800-257-3315 or email

Please Note: If you suspect that you may have an allergy to magnesium, it is recommended that you see your doctor for allergy testing.