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Mag-Ox 400

Mag-Ox Magnesium Supplement, Pharmaceutical Grade Magnesium Oxide 483mg, Most Concentrated Form of Magnesium, 120 Tablets

Based on 9,975 reviews
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$18.03
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Availability: Only 6 left in stock, order soon!
Fulfilled by HerbsDaily
Arrives Sunday, Nov 15
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At a glance

Condition
New
Size
120 Count (Pack of 1)
Pattern
Magnesium
Model
HEALTH212092
Dimensions
4.4 x 2.5 x 2.1 in; 2.4 oz
Weight
2.4 oz
Item Form
Tablet

Features 5

  • Magnesium complex: Mag-Ox 400 contains high potency magnesium for everyday wellness; magnesium oxide works for the body through a variety of functions
  • High potency: Magnesium oxide supplement helps maintain normal muscle and nerve function, promotes heart health, assists in the absorption of calcium and potassium, supports normal metabolism, and can help with occasional constipation
  • Daily support: Magnesium is an essential mineral needed by every cell in the body; each serving contains 483mg of magnesium oxide
  • Easy to swallow: Take 2 tablets daily with food or as directed by a healthcare professional; contains 1 bottle of Mag-Ox 400 with 120 coated magnesium oxide tablets; sugar- and gluten-free

Description

Trusted by consumers for over 50 years, Mag-Ox is 1 pharmacist recommended magnesium supplement brand. Magnesium oxide is used throughout the body for a variety of functions. Magnesium is critical in supporting normal metabolism. Mag-Ox 400 magnesium supplements may help maintain fundamental muscle and nerve function, healthy heart, assist in the absorption of calcium and potassium, and support glucose metabolism. Diuretics, proton pump inhibitors, cisplatin, and cyclosporin may deplete magnesium. For nerve, bone, and heart health, occasional constipation relief, or everyday wellness, add magnesium to your dietary supplements. Magnesium is an essential mineral needed by every cell in the body, and Mag-Ox is at the center of it all. Mag-Ox contains 483mg of magnesium oxide and is available for everyday support. Pharmaceutical grade Mag-Ox 400 has been manufactured to rigorous quality standards for over 50 years. Take 2 Mag-Ox tablets daily with food or as directed by a healthcare professional. Add Mag-Ox to your supplements to support your health everyday. Mag-Ox magnesium oxide tablets come in counts of 60 and 120 for your convenience. US News & World Report and Pharmacy Times, 2026

Specs 19

Product Dimensions 4.4 x 2.5 x 2.1 inches; 2.4 ounces
Item model number HEALTH212092
Manufacturer Prestige Consumer Healthcare
Item Form Tablet
Primary Supplement Type Magnesium
Flavor Unflavored
Product Benefits Energy Management
Diet Type Gluten Free

Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Sunday, Nov 15

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Top Amazon Reviews

Smooth coating no taste easy to swallow
Size: 120 Count (Pack of 1) Pattern Name: Magnesium
I take this daily for my heart and blood pressure. My cardiologist recommended it. I had open heart surgery 18 months ago and had a pacemaker implanted to regulate my heart rate. The magnesium oxide has also helped with my digestive system. I feel like a new person. This particular brand offers a coated product and I prefer it to others I have used. It is not powdery and has a smooth finish that is easy to swallow and has no noticeable taste. I recommend this if your doctor has prescribed it for you! ... show more
Reviewed in the United States on August 22, 2026 by Jane Akins
Just what the Dr. ordered
Size: 120 Count (Pack of 1) Pattern Name: Magnesium
Great price! Much better than the prices at the local pharmacy.
Reviewed in the United States on August 11, 2026 by Dorian
Quality
Size: 120 Count (Pack of 2) Pattern Name: Magnesium
I can’t go without this. This is quality, magnesium supplement. That helps my whole body function better. I normally take it at night before I go to sleep, and I just helps me rest throughout the night.
Reviewed in the United States on August 25, 2026 by Peggy
Best
Size: 120 Count (Pack of 1) Pattern Name: Magnesium
My favorite brand of magnesium oxide. I take 1 before bed and I do feel it helps me sleep better, I feel more relaxed. :)
Reviewed in the United States on August 31, 2026 by Samantha G
Produce strong cramps
Size: 120 Count (Pack of 2) Pattern Name: Magnesium
Review Image by Arlyn Rivas
I had previously posted a review stating that one needed to be cautious with this vitamin if pregnant. The issue was that, at the time, I was also taking prenatal vitamins that contained a slightly higher-than-usual dose of iron—something I must take due to iron-deficiency anemia. It turned out that what was causing my lower abdominal pain was not the magnesium supplement, but rather the iron. Some time later, I stopped taking both supplements; eventually, I went back to testing each one individually. After I stopped taking the prenatals, these pills indeed proved to be quite helpful. However, they do not work if I take the iron as well, since the iron's effect is stronger than the action of this magnesium when taken together. I typically take them at night—around 11:00 PM, just as I am going to sleep—and the following morning I am able to have a bowel movement (except on the occasions when I take the iron, as the iron is what causes my constipation). I wanted to correct the comment I had previously left because I didn't feel it was fair to let it stand, given that since resuming them, they have actually been working for me. I will definitely be buying this brand again. ... show more
Reviewed in the United States on February 18, 2026 by Arlyn Rivas
Nice product
Size: 120 Count (Pack of 2) Pattern Name: Magnesium
Has helped my magnesium levels, doesn’t make me nauseous
Reviewed in the United States on October 3, 2026 by Shirley
Finally, something that works!
Size: 120 Count (Pack of 1) Pattern Name: Magnesium
I've been taking other forms of magnesium, hoping to regulate my plumbing. Taking them along with eating 10 prunes a day did work. My MD recommended magnesium oxide and I tried this brand. It did take about a week or more before it did its job. The only caution I have is that the dose is 483 mg, but the serving size is 2 tablets. At first, I did not realize this, so I was only taking one tablet or 240 mg which did require many additional prunes for proper results. ... show more
Reviewed in the United States on September 13, 2026 by Kate Cohen-Posey
Best Magnesium
Size: 120 Count (Pack of 1) Pattern Name: Magnesium
Best magnesium I have tried, helps me sleep and helps my daily needs to go to the bathroom.
Reviewed in the United States on August 30, 2026 by Jennifer Vivas
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