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Nonprescription Medicines and Products - Antacids and Acid Reducers

Antacids are taken to relieve heartburn or indigestion caused by excess stomach acid. There are several kinds of antacids. Learn what ingredients are in each type so that you can avoid any adverse effects.

  • Sodium bicarbonate antacids (such as Alka-Seltzer and Bromo Seltzer) contain baking soda. Avoid these antacids if you have high blood pressure or are on a salt-restricted diet. Alka-Seltzer contains aspirin, which is linked to Reye syndrome, a rare but serious illness in children.
  • Calcium carbonate antacids (such as Tums) are sometimes used as calcium supplements. These products may cause constipation.
  • Aluminum-based antacids (such as Amphojel) are less potent and work more slowly than other products do. They may also cause constipation. Some may cause calcium loss and should not be taken by women who are past menopause. If you have kidney problems, check with your doctor before you use aluminum-based antacids.
  • Magnesium compounds (such as Phillips' Milk of Magnesia) may cause diarrhea.
  • Combination aluminum-magnesium antacids are less likely to cause constipation or diarrhea than are aluminum-only or magnesium-only antacids. Examples include Maalox, Mylanta, and Riopan. Many of these types of antacids contain simethicone to help break down gas bubbles in your stomach.
  • Antacids with alginic acid (such as Gaviscon) contain a foaming agent that floats on top of the stomach contents. This may help keep stomach juices from coming in contact with your esophagus.

Acid reducers decrease the amount of acid produced by the stomach. They help relieve heartburn. There are several types of nonprescription acid reducers on the market. Examples include H2 blockers (such as famotidine and ranitidine) and proton pump inhibitors (such as lansoprazole and omeprazole). Each has slightly different cautions for use. Read and carefully follow the instructions slideshow.gif included with the package.

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