Magnesium and Interactions PTs Need to Know

Good afternoon, everyone. I'm Dr. Wells here from Nutritional Physical Therapy, and today we're going to talk about magnesium. Magnesium is definitely a supplement of huge interest right now, and I see it a lot on different social media platforms, and I hear a lot of my clients asking about, should I take magnesium, and will it help me with sleep, and will it help me with my digestive system? And the long and the short of it is, it depends, right? So magnesium serves many different roles in the body.

I think there's something like 300 different enzymatic reactions that is reliant on magnesium. Just because there's that many doesn't necessarily mean that we have to supplement with it. It's naturally occurring in things like nuts and seeds, green leafy vegetables, so most of us can get it within our diet.

Now, there are about five different scenarios where I warn my fellow PTs and friends about magnesium supplementation when it comes to clients and patients. I mentioned 4 in my video, but I want to hear from you guys (or you can scroll to the bottom) as to the 5th most common drug class that interacts with magnesium.

The first group would be those that are taking antibiotics, particularly some of the mycin-type group of antibiotics, so like your clindamycin, also your Levaquin, so the quinolone groups, those can also have interactions, and magnesium is taken with that antibiotic. Doxycycline is another group. Mag can actually affect the absorption of those antibiotics and thereby reduce the chances of treating that infection.

So there's some time window that usually it's like two to four to sometimes six hours after taking the antibiotic, it's safe to take the magnesium. My advice to PTs would be, ask the physician, ask the pharmacist, don't rely on your own recommendations.

The second group of meds that should be cautioned when taking magnesium are those that are on bisphosphonates, so like your Fosamax group and things like that. They help absorb calcium and help with bone mineral redeposition. The risk with taking magnesium concurrently with those bisphosphonates is that you actually reduce the uptake of that medicine, which basically reduces its effectiveness. So it's another group I'd tell not to take magnesium unless, again, their pharmacist has double-checked it and their physician has kind of given the green light.

So another group that I caution with this are those that are taking zinc supplements. So zinc actually competes with magnesium's absorption, and so some people will take high doses of zinc, especially around COVID, and it'll suppress their magnesium absorption. Again, if someone suspects they're at risk of magnesium absorption, they can easily ask their physician to run a MAG-RBC to see what their magnesium levels are and if they actually need to add that magnesium supplementation in or not. So word of the wise, zinc and magnesium can sometimes interplay and affect each other.

Another group are people that are taking certain medications, specifically, I always mess this one up, proton pump inhibitors. I was going to say Omiprazole, that's a mouthful for me. But those common PPIs will actually change the gut microbiome in a way that it reduces magnesium. So those are people that are regularly taking that for things like peptic ulcers or reflux. They really should be having their MAG-RBC checked because they actually may be deficient and will need to add in some magnesium.

So anyhow, this is a couple good examples of how magnesium can interplay with certain common medications and how some other common medications can cause insufficiency in magnesium. But overall, I don't blanket recommend magnesium specifically for me. Magnesium actually makes me go to the bathroom too much.

And so it's probably because I eat a lot of green leafy vegetables and nuts and seeds and things. So probably don't really need that much more magnesium in my life. But meanwhile, for others, it helps them sleep better.

They also keep things moving, which isn't bad either. But again, I think everything within reason. And there's specific measurable things that we can have our physician friends and other individuals measure for us. 

Finally, the last class of meds you should caution your patients with would be...

Diuretics! It's generally recommended to avoid taking magnesium supplements while on diuretics because these medications can increase the excretion of magnesium through urine, potentially leading to a deficiency. This happens as diuretics, often called "water pills," work by flushing excess fluid from the body, and unfortunately, essential minerals like magnesium can get swept away in the process. Magnesium is crucial for many bodily functions, and low levels can cause muscle cramps, weakness, and even heart rhythm problems. However, it's important to remember that not all diuretics have the same effect on magnesium. Some, like potassium-sparing diuretics, might actually increase magnesium levels. Therefore, it's crucial for our PT patients to consult their medical doctor or pharmacist before taking any magnesium supplements while on diuretics.

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