BAKERSFIELD, Calif. -- The Food and Drug Administration has issued a warning letter to McNeil Consumer Healthcare Products -- the makers of Tylenol and other over-the-counter medications -- saying the company should have conducted a more thorough investigation when they first learned that consumers were reporting illness related to a musty mildew smell in Tylenol Arthritis capsules.

The smell is believed to come from a chemical used to the treat wooden pellets that protect products during shipping. Patients exposed to the chemical have reported temporary nausea, vomiting, and diarrhea.

McNeil first noticed a trend in consumer complaints in September of 2008, but they did not report the problem to the FDA until a year later.

At the FDA's urging, the company has now conducted a full investigation and is recalling all products that might have been tainted by the chemical.

The expanded recall includes certain batches of regular and extra strength Tylenol, Tylenol PM, Motrin IB, Children's Tylenol and Motrin, Benadryl, and Rolaids.

For full details, go to McNeil's website at www.mcneilproductrecall.com