Children's Hospital Colorado

Milk of Magnesia

Disclaimer: The below information is not intended as a substitute for professional medical advice. It is provided for educational and reference purposes only. You assume full responsibility for how you choose to use this information. Please call your primary care provider or our ParentSmartTM Healthline with any questions. Pediatric nurses are available 24/7 at 720-777-0123.

You can take milk of magnesia to help treat constipation on a short-term basis.

This type of medicine helps pull water into your intestines. This softens the stools.


  • Milk of Magnesia (Liquid): Take 2 tablespoons (30 ml) or 4 tablespoons (60 ml) by mouth. Drink a glass of water (8 oz; 240 ml) after taking this drug. Take this drug only once a day.

Extra Notes and Warnings:

  • This is an over-the-counter (OTC) drug. You can buy it at the drugstore.
  • Do not use this drug if you have kidney disease.
  • Do not use for more than 1 week without talking to your doctor.

Other Names:

  • Magnesium hydroxide

Read the instructions and warnings on the package insert for all medicines you take.