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April 15, 2014

Which antacid should you choose?

Figuring out which antacid will help you find relief from heartburn is not always easy. Here are a few tips to help you make the right choice. However, before using any over-the-counter drug, be sure to consult your pharmacist for help in assessing your symptoms and advice on the most suitable product for you.

What are antacids?

They are medicines that can help alleviate heartburn and acide reflux (gastric reflux or gastroesophageal reflux disease). 

Which antacid should you choose for rapid relief of acid reflux or sour stomach?


Antacids that contain alginate are very effective at easing acid reflux. Products that combine alginate with aluminum, calcium or magnesium (e.g. Gaviscon), create a foam barrier on top of the stomach contents and protect the esophagus from contact with gastric acid.

Stomach acid neutralizers

These antacids relieve both acid reflux and sour stomach by temporarily neutralizing the gastric acid already produced in the stomach. They are generally formulated with one or more of the following salts: calcium, aluminum or magnesium.

Antacids that contain only calcium

Antacids that contain only calcium carbonate (e.g. Tums) provide effective short-term relief. If, however, you take them several times a day or on a regular basis, they can cause what is known as “acid rebound,” a return of symptoms even more intense than prior to taking the medicine.

Antacids that contain both aluminum and magnesium

Antacids that contain both aluminum and magnesium (e.g. Diovol Plus) have the advantage of providing rapid relief of sour stomach and acid reflux by neutralizing gastric acid. Acid neutralizers generally work from 2 to 4 hours, depending on the person and the amount of gastric acid produced.  

Which antacid should you choose for long-term relief of acid reflux or sour stomach?

Some products provide long-lasting relief, but not immediately.

H2 antagonists

H2 antagonists, such as ranitidine (Zantac) and famotidine (Pepcid) act directly on the cells of the stomach to reduce the quantity of acid produced and are effective for both sour stomach and acid reflux. H2 antagonists start to work after about one hour. 

Choose a product that contains:

  • 75 mg of ranitidine (for 4 to 13 hours of relief)
  • 10 mg of famotidine (for 10 to 12 hours of relief)

Proton-pump inhibitors (PPI)

Proton-pump inhibitors such as omeprazole and esomeprazole work by decreasing the amount of acid produced by the stomach for a long-lasting relief of heartburn. They may be suitable for you if you experience gastric symptoms more than twice a week and if antacids do not relieve you. Ask your pharmacist if this product is right for you.

Ingredients to avoid

Products containing a salicylate, such as bismuth subsalicylate, (e.g. Pepto-Bismol or Stomak-Care) or acetylsalicylic acid (e.g. Alka-Seltzer) provide limited effectiveness.

They can also interact with other medications, including certain anticoagulants, antibiotics or diabetes medicine. In addition, they should never be administered to children under the age of 18.

Follow the dosing instructions

Some antacids may look and even taste like candy, but, as Diane Lamarre points out, they must be treated as medicine. It is important to always follow the dosing instructions and pay special attention to the concentration of the product you are using. Remember that there are regular formulas (15 to 30 ml in liquid form or 1 to 4 tablets) and concentrated formulas (10 ml in liquid form or 1 to 2 tablets).

When should you take an antacid?

When taking an antacid, timing is everything. For digestion to occur, the body needs to produce gastric acid. This is why you should wait at least one hour after eating before taking it. Bedtime is another perfect time to take an antacid, since it will have the chance to provide substantive relief.

Ask your pharmacist if you have questions about antacids or over the counter medications.

Source : 
Distinguer reflux gastriques et brûlures d'estomac, Protégez-Vous, November 2012 (In French only)

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