Discover what magnesium hydroxide is used for — from medicine and food to flame retardants and wastewater treatment. Learn its real benefits, uses, and safety tips.

What Is Magnesium Hydroxide Used For?
Ever wondered why you see هيدروكسيد المغنيسيوم on both medicine labels and industrial chemical specs?
That’s because this one compound wears many hats — medical, food, environmental, and industrial.
In this guide, I’ll walk you through exactly what magnesium hydroxide is used for, in plain English — no chemistry degree needed.
A Quick Recap: What Is Magnesium Hydroxide?
Before diving into its uses, let’s define it quickly.
هيدروكسيد المغنيسيوم (ملغ(أوه)₂) is a white, powdery compound made of magnesium, oxygen, and hydrogen.
It’s only slightly soluble in water, which gives it a mild alkaline property — useful in everything from مضادات الحموضة to fireproof materials.
Main Uses of Magnesium Hydroxide
Let’s look at where magnesium hydroxide shows up in real life.
Hint: you’ve probably used it without realizing.
1. In Medicine
One of the most well-known uses is in antacids and laxatives.
If you’ve heard of Milk of Magnesia, that’s magnesium hydroxide suspended in water.
How it works:
It neutralizes stomach acid, easing heartburn and indigestion.
It acts as a gentle laxative, drawing water into the intestines to soften stool.
Common uses:
Relieving constipation
Reducing acid reflux
Treating upset stomach
Why doctors like it:
Non-habit-forming
Works naturally
Fewer side effects compared to harsher laxatives
2. In Food and Nutrition
Magnesium hydroxide also appears in food-grade form, used as a food additive and acidity regulator.
Typical uses include:
Stabilizing pH in processed foods
Acting as an anti-caking agent in powders
Serving as a magnesium supplement
You’ll find it in things like:
Cereal mixes
Powdered drinks
Nutritional tablets
Its role is subtle — it’s there to balance acidity and keep products from clumping.
3. In Flame Retardants
Here’s where it gets interesting.
Magnesium hydroxide is a powerful inorganic flame retardant used in plastics, cables, and building materials.
Why it works:
At high temperatures, it releases water vapor and absorbs heat, which slows down fire spread and reduces smoke.
Benefits:
Non-toxic and halogen-free (unlike many chemical retardants)
Environmentally friendly
Improves fire safety in electrical components and construction materials
Common industries using it:
Cable insulation
Rubber and polymer compounding
Coating and paint formulations
4. In Environmental Protection
High-purity magnesium hydroxide is used to treat wastewater and flue gases.
In wastewater treatment:
Neutralizes acidic waste streams
Precipitates heavy metals
Stabilizes pH in biological treatment systems
In air pollution control:
Used in flue gas desulfurization
Helps capture SO₂ emissions from factories
Why industries prefer it:
Safer alternative to caustic soda or lime
Lower operating costs
Less corrosive to equipment
5. In Industrial Manufacturing
Industrial-grade magnesium hydroxide also plays roles in ceramics, paper, and coatings.
Applications include:
Filler for rubber and plastics
Catalyst base material
Coating pigment to improve whiteness
Paper pulp neutralizer
It’s popular because it’s chemically stable, safe to handle, and cost-effective.
Grades of Magnesium Hydroxide and Their Uses
Not all Mg(أوه)₂ is made equal — its purity and particle size decide where it fits best.
| Grade | Purity Level | Common Use |
| Industrial Grade | ~90% | Wastewater, plastics, الطلاء |
| High Purity Grade | >95% | Flame retardants, catalysts |
| Food Grade | >98% | Food additives, supplements |
| Pharmaceutical Grade | ≥99% | Antacids, laxatives |
If you’re sourcing Mg(أوه)₂, make sure to request a COA (Certificate of Analysis) to verify purity.
Safety and Handling
Magnesium hydroxide is generally safe and non-toxic, but here are a few handling tips:
Avoid dust inhalation in powder form (use masks).
Store in a dry place — it absorbs moisture easily.
Follow labeled dosage for medical use; more isn’t better.
Use certified grades for food or pharma purposes.
In industrial settings, it’s seen as a green, sustainable chemical alternative.
A Quick Story
When I first worked in a flame-retardant plant, we switched from a halogen-based system to هيدروكسيد المغنيسيوم.
The difference was huge — lower smoke, no toxic fumes, and easier compliance with green-material standards.
A few years later, I found the same compound in my bathroom cabinet — labeled “Milk of Magnesia.”
Same chemistry, totally different world.
That’s the versatility of magnesium hydroxide.
FAQs About Magnesium Hydroxide Uses
1. Is magnesium hydroxide safe for long-term use?
For medical use, yes — when taken as directed. But don’t exceed dosage without medical advice.
2. Can it be used in eco-friendly materials?
Absolutely. It’s one of the best halogen-free flame retardants, ideal for green manufacturing.
3. What’s the difference between food-grade and industrial-grade magnesium hydroxide?
Food grade is highly purified and safe for consumption. Industrial grade is meant for chemical processes only.
4. Is it safe for wastewater treatment plants?
Yes. It’s a non-corrosive neutralizer and safer alternative to strong bases like sodium hydroxide.
5. Does magnesium hydroxide occur naturally?
Yes — the mineral form is called brucite, found in metamorphic rocks and seawater deposits.
Conclusion: Why Magnesium Hydroxide Matters
So, what is magnesium hydroxide used for?
Pretty much everything — from medicine and food to fire safety and environmental protection.
It’s one of those rare materials that are effective, safe, and sustainable across industries.
Whether you’re developing medical products, eco-friendly materials, or industrial systems, هيدروكسيد المغنيسيوم deserves a place on your ingredient list.
Because at the end of the day — it’s not just chemistry, it’s smart design.
Magnesium Oxide_Magnesium Hydroxide_Magnesium Carbonate Group-Zehui Group


