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Antacids

What are antacids?

Antacids are drugs that reduce the amount of acid in your stomach or lessen its effect. They are used to treat heartburn, a sour taste in your mouth, indigestion, and stomach ulcers. There are many different forms of antacids.

Most antacids contain at least one of these minerals:

  • aluminum
  • calcium
  • magnesium.

How do they work?

The name antacid means "against acid." Antacids counteract the acid or reduce the amount of acid in the stomach. Some antacids contain additional medicines, such as simethicone, which helps get rid of stomach or intestinal gas.

When are they used?

Many people use antacids to relieve indigestion or a burning pain in the middle of the chest called heartburn. Heartburn refers to the symptoms you feel when acids from your stomach flow backward into the esophagus. The esophagus is the tube that carries food from your throat to your stomach. If you have heartburn often, you may have gastroesophageal reflux disease, also called GERD.

Heartburn may be a sign of an ulcer. Ulcers are irritated areas that develop in the stomach from infection or too much acid. Antacids can be used to treat the pain caused by ulcers. They may also help keep the ulcer from getting worse.

Other problems, such as heart attacks, can have symptoms that are similar to heartburn. Be sure to discuss any new symptoms with your healthcare provider.

What should I watch out for while taking antacids?

The most common side effects of antacids are:

  • constipation (with aluminum-containing antacids)
  • diarrhea (with magnesium-containing antacids)
  • more thirst
  • less appetite.

Many antacids taste chalky. Drink at least 1 glass of water when you take them.

Be careful if you take antacids, especially if you have other health problems. For example, if you are on a low-sodium diet, you need to avoid taking antacids that contain high levels of sodium. Antacids interact with many prescription drugs. If you are taking any prescription medicine, do not take an antacid without first checking with your healthcare provider or pharmacist. Tell your provider if your symptoms do not get better or if they get worse.

Developed by McKesson Corporation
Published by McKesson Corporation.
Last modified: 2007-05-15
Last reviewed: 2007-04-02
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 © 2007 McKesson Corporation and/or one of its subsidiaries. All Rights Reserved.
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