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Laxatives

Magnesium hydroxide (Milk of Magnesia)

Milk of Magnesia an over-the-counter laxative that is used to treat constipation.

 

This medicine is a chalky liquid that comes in a bottle. You can also find it in chewable tablets. It works by bringing extra water into your gut. It makes your stool looser and easier to pass. Make sure you drink enough water (at least 8 ounces) when you take this medicine.

How do I take this medicine?

Take 2-4 tablespoons of milk of magnesia as needed for constipation. Make sure to drink a full 8-ounce glass of water with each dose, because this medication works by drawing water out of your body into your stool.

Milk of magnesia works quickly and often causes diarrhea, so it’s a good idea to be near a bathroom for several hours after taking it.

How long does it take to get relief?

Milk of Magnesia usually takes between 30 minutes to 6 hours to start working.

What are the side effects?

The main side effects of this medication are bloating, gas, and diarrhea or loose stools. Less often, people may notice belly pain or cramps.

Bloating and cramps are usually worse when a person is very constipated. These side effects usually go away after a person has a good-sized bowel movement.

If you have severe belly pain, bloating or diarrhea, talk to your care team. They may suggest a different medication.

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