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Taking antacids

Antacids help to treat heartburn (indigestion). They work by changing the stomach acid that causes heartburn.

You can buy many antacids without a prescription. Liquid forms work faster, but you may like tablets because they are easy to use.

All antacids work equally well, but they can cause different side effects. If you use antacids often and have problems with side effects, talk with your health care provider.

When to Use Antacids

Antacids are a good treatment for heartburn that occurs once in awhile. Take antacids about 1 hour after eating or when you have heartburn. If you are taking them for symptoms at night, DO NOT take them with food.

Antacids cannot treat more serious problems, such as appendicitis, a stomach ulcer, gallstones, or bowel problems. Talk to your provider if you have:

  • Pain or symptoms that do not get better with antacids
  • Symptoms every day or at night
  • Nausea and vomiting
  • Bleeding in your bowel movements or darkened bowel movements
  • Bloating or cramping
  • Pain in your lower belly, on your side, or in your back
  • Diarrhea that is severe or does not go away
  • Fever with your belly pain
  • Chest pain or shortness of breath
  • Trouble swallowing
  • Weight loss that you cannot explain

Call your provider if you need to use antacids on most days.

Side Effects of Antacids

You may have side effects from taking these medicines. Antacids are made with 3 basic ingredients. If you have problems, try another brand.

  • Brands with magnesium may cause diarrhea.
  • Brands with calcium or aluminum may cause constipation.
  • Rarely, brands with calcium may cause kidney stones or other problems.
  • If you take large amounts of antacids that contain aluminum, you may be at risk for calcium loss, which can lead to weak bones (osteoporosis).

Antacids can change the way your body absorbs the other medicines you are taking. It is best to take any other medicine either 1 hour before or 4 hours after you take antacids.

Talk to your provider or pharmacist before taking antacids on a regular basis if:

  • You have kidney disease, high blood pressure, or heart disease.
  • You are on a low-sodium diet.
  • You are already taking calcium.
  • You are taking other medicines every day.
  • You have had kidney stones.

Alternate Names

Heartburn - self-care


Ferrandino MN, Pietrow PK, Preminger GM. Evaluation and medical management of urinary lithiasis. In: Wein AJ, ed. Campbell-Walsh Urology. 10th ed. Philadelphia, PA: Elsevier Saunders; 2011:chap 46.

Katz PO, Gerson LB, Vela MF. Guidelines for the diagnosis and management of gastroesophageal reflux disease. Am J Gastroenterol. 2013;108:308-328.

Update Date 12/2/2014

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