The maker of Tylenol, Motrin, Rolaids, St. Joseph, Benadryl and other over-the-counter medications is recalling certain lots of those drugs following consumer complaints of an unusual moldy, musty, or mildew-like odor that, in a small number of cases, has been associated with symptoms of gastrointestinal distress.  These include nausea, stomach pain, vomiting, or diarrhea.

McNeil Consumer Healthcare has broadened its December recall of Tylenol Arthritis Pain medication to include certain lots of Tylenol, Motrin, Rolaids, Benadryl, St. Joseph and Simply Sleep medications. The list also includes children's medications. The full list is featured at McNeil's Web site as well as on the Web site of the Food and Drug Administration. The affected product lot numbers can be found on the side of the label.

In a press release on the recall, McNeil said it had determined that the smell is caused by the presence of trace amounts of a chemical called 2,4,6-tribromoanisole (TBA) that is sometimes applied to the wood used to build pallets that transport and store product packaging materials. The health effects of TBA have not been well studied but no serious events have been documented in the medical literature, according to McNeil.

But in a report on CNNMoney.com, an FDA official said that the problem was serious enough to warrant a recall sooner. Johnson and Johnson, McNeil's parent company, first learned of the musty odor in 2008. "When something smells bad, literally and figuratively, you aggressively investigate and solve the problem," said Deborah Autor, director of the FDA's compliance office. "The company should have acted faster."

Consumers who purchased any of the recalled OTC drugs are advised to stop using them and to contact McNeil Consumer Healthcare for instructions on a refund or replacement by logging onto the Web site or  by calling 1-888-222-6036. Consumers who have medical concerns or questions should contact their health care provider.