Reflux Remedies: antacids (Tums, Maalox)

What are antacids (Tums & Maalox)? Tums is a brand name for a salt called calcium carbonate. Maalox is brand name for a combination of two salts: aluminum hydroxide and magnesium hydroxide. These three salts are commonly used for relieve of mild heartburn symptoms. Many people use Tums (calcium carbonate) as a calcium supplement for bone health.

How do antacids work?

Antacids like Tums (calcium carbonate) or Maalox do not prevent acid production; instead, they neutralize the excess stomach acid that may be irritating your stomach, esophagus or throat. The antacids, which are basic salts, chemically react with your stomach acid to produce water.

Unlike other heartburn treatments, like Zantac (ranitidine), Tums (calcium carbonate) and Maalox work very quickly. In fact, antacids should provide some relief of your heartburn symptoms within 30 minutes.

While Tums (calcium carbonate) and Maalox work quickly, their effects do not last as long as the effects of Zantac (ranitidine). Tums and Maalox work for 1 hour.

What are the side effects of antacids?

Each antacid salt causes different side effects. Antacids containing calcium carbonate (Tums) or aluminum hydroxide (Alugel, Maalox) cause constipation., which may be treated with laxatives [like Metamucil (psyllium) or Senokot (sennosides)]. Antacids containing magnesium hydroxide (Phillips’ Milk of Magnesia) cause diarrhea. If you have kidney disease or heart failure, contact your doctor before taking antacids on a long-term (> 2 weeks) basis.

Antacids interact with many medications. The calcium (Tums), aluminum or magnesium contained in antacid products bind to numerous drugs (Levothyroxine, Cipro, Neurontin, MacroBID etc). Consequently, antacids prevent the absorption of these and other drugs.  To avoid these drug interactions, separate your antacid doses from doses of other medications by at least 2 hours.

Are antacids safe for pregnant and/or breast-feeding women?

Yes. However, avoid antacids that contain sodium bicarbonate (Alka Seltzer). Sodium bicarbonate may cause fluid retention.


  • Antacids (Tums, Maalox) relieve heartburn symptoms faster than Zantac
  • Antacids may cause diarrhea or constipation
  • Most antacids are safe for pregnant and breast-feeding women

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