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Magnesium Antacids, Oral

mag-NEE-zee-um ant-AS-ids

What are other names for this medicine?

Type of medicine: antacid

Generic and brand names: magnesium hydroxide, oral; Milk of Magnesia; Phillips’ Milk of Magnesia (There may be other brand names for this medicine.)

What is this medicine used for?

This medicine is an antacid that neutralizes stomach acid. It is taken by mouth to relieve heartburn, sour stomach, acid indigestion, and stomach upset. It may also be used to treat gastroesophageal reflux disease (GERD) or stomach and duodenal ulcers.

It may also be used to relieve constipation.

Some antacids contain simethicone, an ingredient that helps get rid of stomach gas.

This medicine may be used to treat other conditions as determined by your healthcare provider.

What should my healthcare provider know before I take this medicine?

Before taking this medicine, tell your healthcare provider if you have ever had:

  • An allergic reaction to any medicine
  • Edema (swelling of the legs and feet)
  • Heart disease
  • Intestinal or stomach problems such as colitis, diverticulitis, or rectal bleeding
  • Kidney or liver disease
  • Phenylketonuria (PKU). Some chewable tablets contain phenylalanine

Tell your healthcare provider if you are on a low sodium or low magnesium diet. Some antacids contain high amounts of sodium or magnesium.

Females of childbearing age: Talk with your healthcare provider if you are pregnant, plan to become pregnant, or are breast-feeding.

How do I take it?

Check the label on the medicine for directions about your specific dose. Take this medicine exactly as directed by your healthcare provider, or according to the manufacturer’s directions. Read all information carefully. For stomach or duodenal ulcers, take the medicine for as long as your healthcare provider tells you. Do not miss doses.

Check with your healthcare provider before using this medicine in children. Some brands should not be used in children at all and some should not be used in children under a specific age.

If you are using chewable tablets, chew them well before swallowing for faster relief.

If you are using fizzing tablets, let them dissolve in water and let most of the bubbling stop before you drink the mixture.

If are using a liquid, shake well before taking. Use a special dose measuring spoon or cup to measure out the correct dose.

Take antacids at least 2 hours before or after taking other medicines to avoid interference.

What if I overdose?

If you or anyone else has intentionally taken too much of this medicine, call 911 or go to the emergency room right away. If you pass out, have seizures, weakness or confusion, or have trouble breathing, call 911. If you think that you or anyone else may have taken too much of this medicine, call the poison control center. Do this even if there are no signs of discomfort or poisoning. The poison control center number is 800-222-1222.

Symptoms of an acute overdose may include: nausea, vomiting, flushing, diarrhea, dizziness, slow heartbeat, drowsiness, coma.

What should I watch out for?

Your healthcare provider may want to see you regularly for checkups if you are taking this medicine for ulcers or another medical condition.

Never take antacids if you have any symptoms of appendicitis or bowel inflammation (severe abdominal pain, vomiting, loose bowel movements, bloody stools). If you have these symptoms, contact your healthcare provider right away.

If you are using this medicine as a laxative, you should have a bowel movement within 30 minutes to 6 hours after taking the medicine. If you have rectal bleeding or do not have a bowel movement after taking this medicine, this could be a sign of a more serious condition. Stop taking the medicine and contact your healthcare provider.

Do not take this medicine as a laxative for more than 1 week unless your healthcare provider tells you to. Tell your healthcare provider if your symptoms do not improve or if they get worse.

Do not take this medicine as an antacid for more than 2 weeks unless your healthcare provider tells you to. Tell your healthcare provider if your symptoms do not improve or if they get worse.

Do not give this medicine to children younger than 12 years old without a healthcare provider’s approval.

If you need emergency care, surgery, or dental work, tell the healthcare provider or dentist you are taking this medicine. It may change certain lab test results.

What are the possible side effects?

Along with its needed effects, your medicine may cause some unwanted side effects. Some side effects may be very serious. Some side effects may go away as your body adjusts to the medicine. Tell your healthcare provider if you have any side effects that continue or get worse.

Life-threatening (Report these to your healthcare provider right away. If you cannot reach your healthcare provider right away, get emergency medical care or call 911 for help.): Allergic reaction (hives; itching; rash; trouble breathing; chest pain or tightness in your chest; swelling of your lips, tongue, and throat).

Serious (report these to your healthcare provider right away): Irregular heartbeat, severe stomach pain, severe nausea and vomiting, extreme weakness or tiredness, mood changes, confusion, muscle pain.

Other side effects: Constipation, nausea, diarrhea, loss of appetite, headache, white or pale bowel movements, stomach cramps.

What products might interact with this medicine?

When you take this medicine with other medicines, it can change the way this or any of the other medicines work. Nonprescription medicines, vitamins, natural remedies, and certain foods may also interact. Using these products together might cause harmful side effects.

Antacids may interact with many prescription drugs. If you are taking any prescription medicine, do not take antacids without checking with your healthcare provider or pharmacist.

If you are not sure if your medicines might interact, ask your pharmacist or healthcare provider. Keep a list of all your medicines with you. List all the prescription medicines, nonprescription medicines, supplements, natural remedies, and vitamins that you take. Be sure that you tell all healthcare providers who treat you about all the products you are taking.

How should I store this medicine?

Store this medicine at room temperature. Keep the container tightly closed. Protect it from heat, high humidity, and bright light.

This advisory includes selected information only and may not include all side effects of this medicine or interactions with other medicines. Ask your healthcare provider or pharmacist for more information or if you have any questions.

Ask your pharmacist for the best way to dispose of outdated medicine or medicine you have not used. Do not throw medicine in the trash.

Keep all medicines out of the reach of children.

Do not share medicines with other people.

Developed by RelayHealth.
Medication Advisor 2015.1 published by RelayHealth.
Last modified: 2014-02-14
Last reviewed: 2014-01-14
This content is reviewed periodically and is subject to change as new health information becomes available. The information is intended to inform and educate and is not a replacement for medical evaluation, advice, diagnosis or treatment by a healthcare professional.
Copyright ©1986-2015 McKesson Corporation and/or one of its subsidiaries. All rights reserved.

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