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Magnesium Hydroxide Chewable tablet

It is used to treat constipation

Generic Name: magnesium hydroxide  |  Brand Name: Ex-Lax

Brand Names: Phillips Milk of Magnesia, Milk of Magnesia, Concentrated Phillips Milk of Magnesia, Ex-Lax Milk of Magnesia, Ex-Lax

What is this medicine?

MAGNESIUM HYDROXIDE (mag NEE zhum hye DROX ide) is a laxative and an antacid. It is used to treat constipation. It is also used to treat acid indigestion, sour stomach, and heartburn.

What should I tell my health care provider before I take this medicine?

They need to know if you have any of these conditions:
  • bowel, intestinal, or stomach disease
  • change in bowel habits for more than 14 days
  • kidney disease
  • low magnesium diet
  • nausea, vomiting
  • stomach pain or blockage
  • an unusual or allergic reaction to magnesium hydroxide, other medicines, foods, dyes, or preservatives
  • pregnant or trying to get pregnant
  • breast-feeding

How should I use this medicine?

Take this medicine by mouth. Chew it completely before swallowing. Follow the directions on the package or prescription label. After taking this medicine, drink a full glass of water. Take your medicine at regular intervals. Do not take your medicine more often than directed.

Talk to your pediatrician regarding the use of this medicine in children. While this medicine may be used in children for selected conditions, precautions do apply.

What if I miss a dose?

If you miss a dose, take it as soon as you can. If it is almost time for your next dose, take only that dose. Do not take double or extra doses.

What may interact with this medicine?

  • antibiotics
  • delavirdine
  • gabapentin
  • lactulose
  • medicines for fungal infections like itraconazole and ketoconazole
  • medicines for osteoporosis like alendronate, etidronate, risedronate and tiludronate
  • medicines for seizures like ethotoin and phenytoin
  • methenamine
  • other magnesium-containing antacids, laxatives or supplements
  • phenothiazines like chlorpromazine, mesoridazine, prochlorperazine, thioridazine
  • quinidine
  • rosuvastatin
  • sodium polystyrene sulfonate
  • sotalol
  • vitamin D

What should I watch for while using this medicine?

Tell your doctor or healthcare professional if your symptoms do not start to get better or if they get worse. Do not treat yourself for constipation with this medicine for more than 1 week. See a doctor if you have black tarry stools, rectal bleeding, or if you feel unusually tired. Do not change to another laxative product without advice.

If you are taking other medicines, leave an interval of at least 2 hours before or after taking this medicine.

To help reduce constipation, drink several glasses of water a day.

What side effects may I notice from receiving this medicine?

Side effects that you should report to your doctor or health care professional as soon as possible:
  • allergic reactions like skin rash, itching or hives, swelling of the face, lips, or tongue
  • confusion
  • feeling faint or lightheaded, falls
  • loss of appetite
  • nausea, vomiting
  • rectal bleeding
  • unusually weak or tired

Side effects that usually do not require medical attention (report to your doctor or health care professional if they continue or are bothersome):

  • chalky taste
  • diarrhea
  • stomach cramps

Where should I keep my medicine?

Keep out of the reach of children.

Store at room temperature between 15 and 30 degrees C (59 and 86 degrees F). Do not freeze. Protect from light and moisture. Throw away any unused medicine after the expiration date.

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.


Last Updated: July 06, 2009
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