Examples
| Brand Name | Chemical Name |
| Maalox, Gaviscon | aluminum hydroxide and magnesium carbonate |
| Mylanta | aluminum hydroxide, magnesium hydroxide, and simethicone |
| Rolaids, Tums | calcium carbonate |
Antacids are available without a prescription in liquid, chewable tablet, chewing gum, and dissolving tablet forms to be taken by mouth.
How It Works
Antacids make stomach juices less acidic. Less acid in your stomach can make you feel better and reduce your symptoms.
Why It Is Used
- Antacids may be used to provide short-term relief of ulcer symptoms during the first few days after a person begins taking an acid reducer, such as a proton pump inhibitor. The antacid may be used until the acid reducer is able to control the symptoms.
- Antacids, when taken for 6 to 8 weeks, may sometimes be used to help heal an ulcer that is not caused by a Helicobacter pylori (H. pylori) infection or by NSAIDs.
How Well It Works
When used regularly at higher doses, an antacid may heal an ulcer about as well as a histamine H2 blocker. An antacid does not heal an ulcer as quickly as a proton pump inhibitor.
Side Effects
The active ingredients in antacids vary, with the following cautions for each:
- Sodium bicarbonate (baking soda) is not recommended for people who must reduce the sodium (salt) in their diet.
- Calcium carbonate (such as Rolaids or Tums) can stimulate acid rebound in some people. Acid rebound causes the stomach to produce even more acid, making heartburn worse. However, this is very rare. It also may cause constipation in some people.
- Magnesium-containing antacids (such as Maalox, Gaviscon, or Mylanta) can cause diarrhea. If used too often by people who have kidney problems, these antacids can lead to too much magnesium in the blood.
- Aluminum-containing antacids (such as Maalox, Gaviscon, or Mylanta) can cause constipation. If used too often by people with chronic kidney failure, these antacids can lead to too much aluminum in the blood.
Some antacid preparations (such as Maalox, Gaviscon, or Mylanta) combine active ingredients to balance side effects. For example, antacids may contain both magnesium and aluminum to prevent diarrhea or constipation.
See Drug Reference for a full list of side effects. (Drug Reference is not available in all systems.)
What To Think About
While antacids often are able to reduce the symptoms of an ulcer, acid reducers are more effective and provide symptom relief for a longer period of time. An antacid taken at bedtime may not control symptoms throughout the night; a person may still be awakened at night with pain from an ulcer.
Antacids that contain calcium carbonate (such as Rolaids or Tums) may help boost calcium intake, an important benefit for women concerned about developing osteoporosis.
Some antacids may decrease the absorption of iron, certain antibiotics, digoxin (Lanoxin), and other medications.
Antacids that contain sodium bicarbonate should not be taken by pregnant women because they can lead to fluid retention. Antacids that contain calcium carbonate (such as Tums) are safe to take during pregnancy. Discuss using antacids with your doctor first.
Antacid therapy is usually less expensive than other treatments.
Liquid antacids may relieve symptoms faster than other forms of antacids.
Antacids and acid reducers should not be taken within 2 hours of each another because the antacid will cause the acid reducers to take effect more slowly.
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Credits
| Author | Colleen Cronin |
| Author | Ralph Poore |
| Editor | Susan Van Houten, RN, BSN, MBA |
| Associate Editor | Michele Cronen |
| Associate Editor | Terrina Vail |
| Primary Medical Reviewer | Kathleen Romito, MD - Family Medicine |
| Specialist Medical Reviewer | Andrew H. Soll, MD - Gastroenterology |
| Last Updated | January 12, 2006 |
Ralph Poore
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