Antacids are medicines used to neutralize stomach acid and reduce heartburn, bloating, upset stomach, and other digestive symptoms associated with stomach acid. While antacids are generally thought to be a low-risk solution for unpleasant digestive symptoms, it is also important for patients to know that as with all medications, there are some potential risks associated with antacid use. Popular types of antacids are those containing aluminum or magnesium hydroxide (including brand names Maalox, Mylanta, and Rulox) and those containing calcium carbonate (including brand names Alka-Mints, Rolaids Calcium Rich, and Tums). Some also contain sodium carbonate or bismuth subsalicylate. Calcium carbonate antacids are also used as a calcium supplement.
Each type of antacid has its own set of potential side effects and dangers. Antacids containing magnesium and sodium bicarbonate can have laxative properties if taken for long periods of time or in large quantities. Alternately, aluminum and calcium carbonate, as well as bismuth subsalicylate can cause constipation. In rare cases, urinary effects, headaches, nausea, muscle weakness and appetite changes have been noted, as well, and the occasional patient is allergic to antacid components, and should steer clear of them to avoid a potentially life-threatening allergic reaction. But usually, these results can be avoided by not exceeding the dosage recommendation and remaining vigilant about allergy concerns.
A potential risk of antacids that particularly concerns many medical professionals, however, is that, if taken in the long term, antacids may cause the stomach to produce more acid, leading to a downward spiral of symptoms, with more acid causing worse indigestion as time goes on.
There are a few specific reasons why this may be the case. First, stomach acid is needed to break down calcium carbonate, so if excessive amounts of calcium carbonate antacids are in the stomach, more acid will be produced to break it down. Also, for digestion to work properly, the stomach needs to be producing and maintaining acidity; if an antacid is taken too zealously and reduces the acid level to below normal, rather than helping to level it off, the stomach will respond with a resurgence of acid. Finally, antacids can only help to neutralize acid in the stomach, not to change chronic underlying digestive problems, such as stress, diet, or disorders leading to acid production, and failure to treat underlying problems may lead to those problems growing worse in time.
At the same time, many people suffer from periodic indigestion, and only some of those people have symptoms or conditions severe enough to call for a prescription medication less prone to this sort of vicious cycle. The best approach for patients who use antacids more than occasionally is to go over any troubling digestive symptoms with a medical care professional, who can help them decide when, if, and how much antacid use is appropriate, and check in to make sure that negative effects are not outweighing positive effects.