A U.S. congressional committee is investigating Johnson & Johnson's recent recall of Children's Tylenol and other over-the-counter pediatric medicines.

The House of Representatives Committee on Oversight and Government Reform opened the investigation after J&J took 40 widely-used children's pain and allergy medications off the market, saying some may have a higher concentration of their active ingredients while others may be contaminated.

The lawmakers are questioning the adequacy of the U.S. Food and Drug Administration's inspection procedures and whether J&J's McNeil Consumer Healthcare unit failed to investigate consumer complaints that could have identified the contamination problems, according to a committee press release.

The panel expects to hold a hearing in the coming weeks.

We are deeply concerned about the recall of popular pediatric medications widely used by infants and children across the country, Committee Chairman Edolphus Towns, a New York Democrat, and the panel's ranking Republican, Darrell Issa of California, said in the release.

The FDA issued a damning report on Tuesday, saying inspectors found thick dust, grime and contaminated ingredients at the J&J plant that produces Children's Tylenol and dozens of other products recalled last week.

(Reporting by Lewis Krauskopf; editing by John Wallace)