WASHINGTON (AP) -- Federal health regulators are investigating hundreds of consumer complaints involving children's medicines recalled by Johnson & Johnson last month, according to a congressional memo.

The Food and Drug Administration has not directly linked any of the reports to flaws with the company's products.

J&J recalled more than 40 varieties of children's cold medicines last month after FDA inspectors discovered a slew of manufacturing problems at a Pennsylvania facility. The company's third recall in the past year triggered a flurry of criticism from Washington lawmakers, who will question company management at a hearing Thursday.

A spokeswoman for J&J declined Wednesday to comment on the congressional memo. Late Tuesday the company posted a statement on its Web site saying it would restore its public image by restructuring management and overhauling manufacturing operations.

"McNeil is taking steps to bring its operation back to a level of quality that Johnson & Johnson demands of its companies, and that the public rightly expects of us," read the statement.

Since the April 30 recall, the FDA has received hundreds of reports of complications with J&J products, including seven deaths, according to a memo distributed to congressional staffers. The memo was obtained Wednesday by the Associated Press.

FDA is investigating whether the problems are linked to flaws in J&J products, which include infant Tylenol, Benadryl and Motrin.

"At this time, FDA is not aware of any child being harmed by taking one of the recalled products," states the congressional memo.

FDA deputy commissioner Joshua Sharfstein is scheduled to testify. Sharfstein is expected to provide new detail on problems uncovered at J&J's Fort Washington, Penn. plant.

FDA inspectors found that J&J failed to investigate medications that had potentially unsafe potency levels, according to FDA documents cited in the memo. While J&J rejected three batches of Infant Tylenol found to be overly potent, the company failed to check seven other batches at risk for the problem.

In another instance, FDA found that J&J did not recall a batch of products potentially infected with bacteria. The products were in distribution last fall and could still be on store shelves, according to FDA.

Colleen Goggins, J&J's president for McNeil consumer products, will testify before the House Committee on Oversight and Government on J&J's handling of the recall.

J&J, which is based in New Brunswick, N.J., has long enjoyed a sterling public image, even taking first place last year in a poll of corporate reputations.

That positive image is due in part to J&J's handling of past product recalls.

The company's response to a 1982 cyanide tampering scare in Chicago that killed seven people is considered a textbook example of how to deal with a brand crisis. J&J had its sales force remove 264,000 Tylenol bottles from store shelves and consumers were urged to return any Tylenol they had for a safe bottle.

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