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Magnesium citrate

Generic Name: magnesium citrate (mag NEE see um SIH trate)
Brand Name: Citrate of Magnesia, Citroma, Citroma Cherry, Citroma Lemon

Medically reviewed on September 21, 2017

What is magnesium citrate?

Magnesium is a naturally occurring mineral that is important for many systems in the body, especially the muscles and nerves. Magnesium citrate also increases water in the intestines.

Magnesium citrate is used as a laxative to treat occasional constipation.

Magnesium citrate may also be used for purposes not listed in this medication guide.

Important Information

Follow all directions on your medicine label and package. Tell each of your healthcare providers about all your medical conditions, allergies, and all medicines you use.

Before taking this medicine

Ask a doctor or pharmacist if it is safe for you to take this medicine if you have other medical conditions, especially:

  • kidney disease;

  • a sudden change in bowel habits that has lasted longer than 2 weeks;

  • stomach pain, nausea, vomiting; or

  • if you are on a low-magnesium or low-potassium diet.

It is not known whether magnesium citrate will harm an unborn baby. Do not use this medicine without a doctor's advice if you are pregnant.

It is not known whether magnesium citrate passes into breast milk or if it could harm a nursing baby. Do not use this medicine without a doctor's advice if you are breast-feeding a baby.

How should I take magnesium citrate?

Use exactly as directed on the label, or as prescribed by your doctor. Do not use in larger or smaller amounts or for longer than recommended.

Take magnesium citrate on an empty stomach, at least 1 hour before or 2 hours after a meal.

Measure liquid medicine with the dosing syringe provided, or with a special dose-measuring spoon or medicine cup. If you do not have a dose-measuring device, ask your pharmacist for one.

Take this medicine with a full glass of water.

Magnesium citrate should produce a bowel movement within 30 minutes to 6 hours after you take the medicine.

Call your doctor if your symptoms do not improve after 7 days of treatment, or if the medicine produces no results. Not having a bowel movement after using a laxative may be a sign of a condition more serious than occasional constipation.

Store at room temperature away from moisture and heat.

What happens if I miss a dose?

Since magnesium citrate is used when needed, you may not be on a dosing schedule. If you are on a schedule, use the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not use extra medicine to make up the missed dose.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

What should I avoid while taking magnesium citrate?

Avoid taking any other medicines within 2 hours before or 2 hours after you take magnesium citrate. Laxatives can make it harder for your body to absorb certain other drugs.

Magnesium citrate side effects

Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Stop using magnesium citrate and call your doctor at once if you have:

  • no bowel movement within 6 hours after taking the medicine;

  • pain with bowel movements, rectal bleeding;

  • watery diarrhea, nausea, vomiting, severe stomach pain;

  • painful or difficult urination;

  • flushing (warmth, redness, or tingly feeling);

  • a light-headed feeling, like you might pass out;

  • weak or shallow breathing, slow heartbeats; or

  • muscle weakness, increased thirst.

Common side effects may include:

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

See also: Side effects (in more detail)

Magnesium citrate dosing information

Usual Adult Dose for Constipation:

240 mL orally one time.

Usual Pediatric Dose for Constipation:

< 6 years: 0.5 mL/kg orally up to a maximum of 200 mL. May repeat every 4 to 6 hours until stools are clear.

6 to 12 years: 100 to 150 mL orally one time.

What other drugs will affect magnesium citrate?

Other drugs may interact with magnesium citrate, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell each of your health care providers about all medicines you use now and any medicine you start or stop using.

Further information

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.

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