FORT WASHINGTON, Pa. — McNeil Consumer Healthcare has issued a voluntary recall of certain lots of over-the-counter medications, including products from its Tylenol, Motrin, Benadryl, Rolaids, St. Joseph and Simply Sleep brands.

The company said Friday that in consultation with the Food and Drug Administration, it has initiated a recall of those lots of products in the Americas, the United Arab Emirates and Fiji after an investigation of consumer reports of an unusual moldy, musty or mildew-like odor that, in some cases, was associated with symptoms such as nausea, stomach pain, vomiting or diarrhea.

Based on the investigation, McNeil Consumer Healthcare — a division of McNeil-PPC Inc. — has determined that the smell stems from trace amounts of a chemical called 2,4,6-tribromoanisole (TBA), which the company said can result from the breakdown of a chemical that is sometimes applied to wood used for pallets that transport and store product packaging materials. The health effects of the chemical have not been well-studied, but no serious events have been documented in the medical literature, according to McNeil. A small number of the product lots being recalled were associated with complaints of an odor, and some of those lots were found to contain traces of TBA, the company said.

McNeil Consumer Healthcare added that last month it recalled all lots of Tylenol Arthritis Pain 100-count with EZ-Open Cap related to this issue. The company said it has now applied broader criteria to identify and remove all product lots that it thinks might be affected, even if they have not been the subject of consumer complaints.

McNeil, too, said it is continuing its investigation into this issue and is taking further actions that include halting shipment of products produced using materials shipped on these wood pallets and requiring suppliers who ship materials to its plants to discontinue the use of those pallets.

Products in the recall include certain sizes, varieties and lots of Children’s Motrin caplets and chewables; Children’s Tylenol meltaways; Benadryl tablets; Extra Strength Tylenol caplets, Cool Caplets, EZ Tablets, rapid-release gelcaps and tablets; Motrin IB caplets and tablets; Regular Strength Tylenol caplets and tablets; Rolaids chewables; Simply Sleep caplets; St. Joseph chewables and tablets; Tylenol 8-Hour caplets; Tylenol Arthritis caplets and geltabs; and Tylenol PM caplets, geltabs and rapid-release gelcaps.

The affected product lot numbers for the recalled products can be found on the side of the bottle label. Consumers who purchased products from the lots identified in this recall should stop using the product and contact McNeil Consumer Healthcare for instructions on a refund or replacement, according to the company. For more information on the recall, consumers can call 1-888-222-6036 or go online to www.mcneilproductrecall.com.