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Magnesium Hydroxide

Medically reviewed by Last updated on Feb 21, 2019.

Dosage form: liquid
Ingredients: MAGNESIUM HYDROXIDE 400mg in 5mL
Labeler: Rebel Distributors Corp
NDC Code: 21695-903

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Milk of Magnesia Drug Facts

Active ingredient

Magnesium Hydroxide 400mg


Saline Laxative / Antacid

Keep Out of Reach of Children

In case of overdose, get medical help or contact a Poison Control Center right away.


Laxative: relieves occasional constipation; generally produces a bowel movement in 1/2 to 6 hours.

Antacid: relieves heartburn, sour stomach & acid indigestion.


Ask a doctor before use if you have:

° kidney disease ° a magnesium-restricted diet ° stomach pain, nausea or vomiting ° a sudden change in bowel habits that lasts over 2 weeks

Ask a doctor or pharmacist before use if you are taking any other drug.

° antacids may interact with certain prescription drugs ° laxatives may affect how other drugs work, so should be taken 2 or more hours before or after other drugs.

When using this product as an antacid, it may have a laxative effect.

Stop use and ask a doctor if ° you have rectal bleeding or no bowel movement after using this product. These could be signs of a serious condition ° You need to use a laxative for more than 1 week ° symptoms last more than 2 weeks.

If pregnant or breast-feeding, ask a health professional before use.

Other Information

each 5 mL teaspoon contains: magnesium 165mg and sodium 2 mg

store at room temperature

protect from freezing

keep tightly closed


Laxative: ° shake well before using

° drink a full glass (8 ounces) of liquid with each dose

° may be taken as a single or divided dose

Antacid: ° do not take more than 12 teaspoons in 24 hours

° do not use maximum dosage for more than 2 weeks


adults and children 12 years and older: 2 to 4 tablespoons

children 6 to under 12 years: 1 to 2 tablespoons

children 2 to under 6 years: 1 to 3 teaspoons

children under 2 years: ask a doctor


adults and children 12 years and older: 1 to 3 teaspoons with water, up to 4 times daily

children under 12 years: ask a doctor

Inactive ingredients

flavor, purified water, saccharin sodium, sodium hypochlorite

Questions or comments? Call 1-800-645-2158, 9 am - 5 pm EST, Monday-Friday

Package/Label Principal Display Panel

magnesium hydroxide liquid
Product Information
Product TypeHUMAN OTC DRUGItem Code (Source)NDC:21695-903(NDC:0536-2470)
Route of AdministrationORALDEA Schedule    
Active Ingredient/Active Moiety
Ingredient NameBasis of StrengthStrength
Inactive Ingredients
Ingredient NameStrength
#Item CodePackage Description
1NDC:21695-903-16473 mL in 1 BOTTLE
Marketing Information
Marketing CategoryApplication Number or Monograph CitationMarketing Start DateMarketing End Date
OTC monograph finalpart33103/22/2010
Labeler - Rebel Distributors Corp (118802834)
Rebel Distributors Corp118802834RELABEL, REPACK

Rebel Distributors Corp