A group of physicians and families called on US regulators Tuesday to warn the public about a rare but potentially fatal set of skin reactions linked to taking the painkiller ibuprofen.

The group filed a petition with the US Food and Drug Administration asking it to strengthen labels on Advil and other ibuprofen-based drugs to warn doctors and consumers that the widely sold products can increase the risk of skin reactions, including serious conditions like Steven Johnson Syndrome (SJS) and toxic epidermal necrolysis (TEN).

SJS occurs in approximately four in every one million ibuprofen users. Those who continue taking the drug can develop TEN, which causes severe skin sloughing and is fatal in nearly one third of affected patients.

“All we’re asking for is a few sentences on the box. We’re not asking that the drug be withdrawn,” said Dr. Michael Nicar, a toxicologist from Baylor University Medical Center in Dallas.

Nicar signed the petition along with three other physicians, all of whom have acted as expert witnesses in lawsuits against ibuprofen manufacturers. Three families that are suing drug companies, alleging that their children were injured or killed after using ibuprofen, also signed the document.

The petition also calls on the FDA to launch an investigation into allegations that ibuprofen manufacturers withheld information on the risks of dangerous reactions to their products.

Drug reactions cause an estimated 5000 hospitalizations and tens of thousands of outpatient visits for SJS, TEN, and related disorders each year, according to a study published last month in the journal Pharmacoepidemiology and Drug Safety.

Approximately half of all SJS cases are caused by viruses, while the rest are caused by a variety of drugs, including anticonvulsants and antibiotics.

Ibuprofen does not generally cause the disorder in adults but can in children, said Dr. Roger E. Salisbury, a professor of surgery at Westchester Medical Center in Valhalla, New York, who also signed the petition.

“There are a lot of physicians who are not even familiar with this association,” he said. Doctors and patients should know to stop the drugs immediately if a rash appears, he added.

Ibuprofen, found in popular non-prescription drugs such as Advil and Motrin, is widely used for lowering fevers in children. Some ibuprofen products marketed in Europe carry label warnings of rare severe skin reactions, though their American counterparts do not, the group said.

“We’re merely asking the FDA to look at this and tighten up the warnings,” Salisbury said.

Ibuprofen drug makers are facing several lawsuits over alleged injuries to children caused by ibuprofen products.

“If my doctor and my husband and I had known about these risks of SJS and TEN we would have never given her Children’s Advil,” said Darlene Kiss, who sued Advil maker Wyeth Consumer Healthcare last month alleging that the drug caused the death of her 3-year-old daughter Heather in March 2003.

Wyeth spokesman Doug Petkus declined to comment on any litigation facing the company, but said that Advil and Children’s Advil already refer to the potential for severe allergic reactions and that the current labeling is “sufficient.”

“They’re safe when taken as directed,” he said.

McNeil Consumer & Specialty Products, a division of Johnson & Johnson that markets several child and adult forms of ibuprofen under the brand name Motrin, issued a statement stressing that SJS is rare and can have a variety causes.

“Children’s Motrin, when used as directed, is safe and efficacious,” said company spokesperson Kathy Fallon.

The petition was timed to coincide with the scheduled Wednesday start of FDA hearings into the safety and effectiveness of nonsteroidal anti-inflammatory drugs, including ibuprofen and COX-2 inhibitors, such as Celebrex (celecoxib) and Bextra.