The makers of Tylenol will be pulling out 21 Tylenol liquid products manufactured between April 2008 and June 2008 from warehouses and retail stores as a precaution against possible contamination.

McNeil Consumer Healthcare, Tylenol's manufacturer, informed that a bacterium was detected in an inactive ingredient. Although that ingredient wasn't used in any packaged final products, it was produced along with other products.

Therefore, the manufacturer has decided to recall all products from the market that utilized any of the raw materials at the same time as the raw material that tested positive for the bacteria, in consultation with the Food and Drug Administration.

McNeil also told that scientific literature about the bacteria says that orally consuming a contaminated pharmaceutical does not trigger infection using products like nasal spray have caused infections.

"Our stomachs have a lot of enzymes that help destroy the bacteria," said Daryl DePestel, a professor at Univesity of Michgan's College of Pharmacy.

He also said that maximum foods contain bacteria but they are killed inside the body. However, through a nasal spray the bacteria find their way into the lungs bypassing the body's safety mechanisms.

He said that the infection can be severe for patients suffering with lung disease but there is a very low-risk factor involved.

Parents have been advised to contact their health providers by McNeil.