The Food and Drug Administration (FDA) is warning consumers to carefully read the label of over-the-counter drugs to avoid any drug interactions. Specifically, the agency has received reports of consumers confusing different Maalox products containing different active ingredients intended for the relief of different symptoms that have the potential for serious side effects.

The issue involves Maalox Total Relief, an upset stomach reliever and anti-diarrhea medication, being mistaken for the traditional Maalox liquid antacids, Maalox Advanced Regular Strength and Maalox Advanced Maximum Strength, commonly taken for acid indigestion, heartburn, sour stomach, upset stomach, and pressure and bloating, also known as gas.

The active ingredient in Maalox Total Relief is bismuth subsalicylate, which is chemically related to aspirin and may cause similar harmful side effects such as bleeding. Thus, Maalox Total Relief is not appropriate for individuals with a history of gastrointestinal ulcer disease or a bleeding disorder. It also should not be taken by children and teens if they are recovering from a viral infection, nor by those who are taking certain medications such as oral antidiabetic drugs (OADs), anticoagulation drugs (blood thinners) such as warfarin (coumadin) and clopidogrel (Plavix), non-steroidal anti-inflammatory drugs (NSAIDS), and other anti-inflammatory drugs.

To date, the FDA has received five reports of consumers taking Maalox Total Relief when they intended to take the antacid Maalox instead.

Novartis Consumer Health Inc., the company that makes both Maalox products, has agreed to change the name of Maalox Total Relief to one that does not include the word “Maalox,” and will change the drug’s packaging to avoid further confusion. The renamed product is expected to be available for sale in September 2010. Until then, the FDA is advising consumers and health care professionals to carefully check the labels of all Maalox products to ensure the appropriate product is being selected for the patient’s symptoms.

Consumers with questions can refer to this consumer information sheet from Novartis.