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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 9,918 reviews
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Availability: In Stock.
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Size: 120 Count (Pack of 1)


Pattern Name: Magnesium


Features

  • TRUSTED RELIEF: Mag-Ox is the #1 doctor recommended brand; Trusted by consumers for over 50 years
  • HIGH POTENCY: Pharmaceutical grade, high potency magnesium supplement
  • DIETARY INTAKE: Approximately half of Americans don't get enough magnesium in their diets
  • DAILY SUPPORT: Take daily to help maintain healthy heart rhythms, normal muscle and nerve function*
  • OPTIMAL HEALTH: Magnesium is an essential mineral needed by every cell in the body*

Description

Trusted by consumers for over 50 years, Mag-Ox is a high potency dietary supplement made from Magnesium Oxide. Mag-Ox is the 1 doctor recommended magnesium supplement brand used throughout the body for a variety of functions. Magnesium is critical in helping convert carbohydrates, protein and fat into energy – helping support the formation and release of energy from cells. Normal magnesium intake helps maintain normal muscle and nerve function as well as maintain healthy heart rhythms. Magnesium is an essential mineral needed by every cell in the body and Mag-Ox is at the center of it all. Mag-Ox tablets contain 483mg of magnesium oxide and are gluten free. Take 2 tablets daily with food or as directed by a healthcare professional. Mag-Ox magnesium tablets come in counts of 60, 120, and 240 for your convenience. These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.

Product Dimensions ‏ : ‎ 4.4 x 2.5 x 2.1 inches; 2.4 ounces


Item model number ‏ : ‎ HEALTH212092


Date First Available ‏ : ‎ October 15, 2008


Manufacturer ‏ : ‎ Prestige Consumer Healthcare


Best Sellers Rank: #3,453 in Health & Household (See Top 100 in Health & Household) #76 in Magnesium Mineral Supplements #823 in Sales & Deals


#76 in Magnesium Mineral Supplements:


#823 in Sales & Deals:


Customer Reviews: 4.7 4.7 out of 5 stars (9,918)


Item Form: Tablet


Primary Supplement Type: Magnesium


Flavor: Unflavored


Product Benefits: Energy Management


Diet Type: Gluten Free


Concentration: 483 Mg


Unit Count: 120 Count


Number of Items: 1


Item Weight: 2.4 ounces


Brand Name: Mag-Ox 400


Age Range Description: Adult


Manufacturer: Prestige Consumer Healthcare


UPC: 760569494121 301650400005


Global Trade Identification Number: 05, 21


Model Number: HEALTH212092


Manufacturer Part Number:


Material Type Free: Alcohol Free


Allergen Information: Gelatin


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Sep 13 – Sep 14

This item is non-returnable:

Non-returnable due to Food safety reasons

View our full returns policy here.

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Top Amazon Reviews

    • Price is great for twin pack Great product if you take other Magnisum products, try this.
Size: 120 Count (Pack of 2) Pattern Name: Magnesium
I love this twin-pack for the price. I've been taking Magnesium for about 3 years. Retains good heart health and rhythm function, muscle and nerve function, helps with calcium and potassium absorption, and helps support glucose metabolism.
Reviewed in the United States on July 16, 2025 by KG
    • Great supplement
Size: 120 Count (Pack of 2) Pattern Name: Magnesium
Best I found
Reviewed in the United States on December 31, 2025 by steve chatot
    • I recommend
Size: 60 Count (Pack of 1) Pattern Name: Magnesium
These work great! I highly recommend
Reviewed in the United States on January 21, 2026 by amy deblasio
    • Balance electrolytes with magnesium supplements.
Size: 120 Count (Pack of 1) Pattern Name: Magnesium
Magnesium products are used to balance a person's electrolyte panel and promote healthy cardio pressure balance. The Mag-Ox product, in particular, is a good source of magnesium to promote balance among calcium, potassium, sodium, and magnesium ions. People are often deficient in magnesium and potassium relative to the other ions. This product is designed to break apart and dissolve more quickly than some other products. If you used this product some years ago, then you may have noticed a flakiness in the pill structure. The company has addressed this problem and made them smoother and easier to swallow. Other absorbable magnesium products are available on Amazon and can be used in addition to Mag-Ox. In particular, magnesium taurate, magnesium glycinate/lysinate, magnesium malate, and magnesium citrate. If a magnesium product causes some stomach upset or does not assist you in reaching a magnesium electrolytic balance, then trying another product would be advisable. Work with your healthcare professional to determine which product works best. Supplements should not be taken everyday and a 100% of the RDA (recommended dietary allowance) may also be unnecessary. Skipping to every other day at most at and/or about 50% RDA at most seems to work best for many people. Magnesium products produce other outcomes in addition to promoting magnesium balance. For example, magnesium taurate tends to promote cognitive calming. Magnesium malate and lysinate/glycinate promotes muscle relaxation. Magnesium citrate is quickly absorbed, and its effects may be quickly noticed. Overall, the taurate, malate, and lysinate/glycinate products are balancing alternatives to magnesium oxide. The best time-of-day to take Mag-Ox or other magnesium supplements is in the late evening before retiring. A snack and some milk also protects your stomach from upset and slows the overnight absorption of the product. Since magnesium products have a calming effect, these tend to promote a good night sleep as well. One last comment about using Mag-Ox, magnesium oxide. Be careful if you also take statins. The research I've reviewed indicates that magnesium oxide interferes with the absorption of statins and dulls its cholesterol lowering effectiveness. Statins are usually taken with the major meal of the day—lunch or dinner. If you take statins with your evening meal, then wait at least two or more hours later in the evening before you take these supplements. ... show more
Reviewed in the United States on September 28, 2018 by Deebz
    • 💯
Size: 120 Count (Pack of 1) Pattern Name: Magnesium
Best thing the Dr said to take its cheap and helps with cramps
Reviewed in the United States on January 12, 2026 by scott
    • Quality product
Size: 120 Count (Pack of 1) Pattern Name: Magnesium
Quality product
Reviewed in the United States on December 19, 2025 by Michelle C
    • Fixed my leg cramps
Size: 120 Count (Pack of 1) Pattern Name: Magnesium
Premenopauses kicking my butt, leg cramps made it impossible to sleep. This magnesium makes me feel like im 30 again. Well when I sleep. I don't wake up screaming from a Charlie horse.
Reviewed in the United States on February 6, 2026 by mcc85
    • Easier to use. Smaller than the others
Size: 60 Count (Pack of 1) Pattern Name: Magnesium
I would give these 10 stars if I could. Other mag 400 pills are HUGE & impossible to swallow. Cutting them in half is like trying to swallow sand. These are far smaller.
Reviewed in the United States on January 8, 2026 by Christine2152

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