Recently filed court documents show the makers of Tylenol planned to enlist the White House and lawmakers to block the Food and Drug Administration from imposing tough new safety restrictions on acetaminophen, the iconic painkiller’s chief ingredient.

An executive with McNeil Consumer Healthcare – which counts Tylenol as its flagship product – told the board of directors for parent company Johnson and Johnson about a campaign to “influence the FDA” and block recommendations made by an agency advisory panel in 2009.

After Dr. Janet Woodcock, the FDA’s top drug regulator, put off meeting with McNeil executives, the company’s president, Peter Luther, sent out an August 2009 email.

“We’re being too nice and too worried about stepping on FDA’s toes. It may be time to let members of Congress to put some pressure on FDA,” Luther wrote to other top executives. ”We have to make this our top priority and pull out all stops.”

Acetaminophen is considered safe when taken as directed. But in higher doses, the drug can cause liver damage and death. Studies show the drug is the leading cause of acute liver failure in the U.S., with fatalities increasing seven-fold in the decade between 1995 and 2005 to more than 200 a year.

“’We’re going to involve key opinion leaders, and we’re going to get them to help us influence the FDA to disregard what the advisors said,’” a plaintiff’s lawyer told a New Jersey court late last month, describing the contents of internal corporate documents.

The previously unreported lobbying campaign was disclosed as part of a trial scheduled to start today in Atlantic City that promises to draw new scrutiny to McNeil’s efforts to protect its painkiller from additional regulation and disclosures about the full extent of its risks.

The case pits McNeil against Regina Jackson, a New Jersey state employee who claims she was hospitalized with elevated liver enzymes after inadvertently exceeding the daily recommended dose for Extra Strength Tylenol for a couple of days.

The Atlantic City case is being watched closely as it is the first to come to trial of more than two hundred lawsuits currently pending in state and federal courts that allege McNeil knew its drug was potentially dangerous while promoting its safety.