Accidental pediatric exposures to the gels can occur when the “consumer forgets to wash their hands or forgets to cover a treated area, and then has close contact with the child, or may have not waited for their skin to dry and then picks up a child,” Dr. Dianne Murphy, the FDA’s director of the Office of Pediatric Therapeutics within the Office of the Commissioner, said during a Thursday afternoon press conference.

Over time, these exposures can lead to premature and/or abnormal development of male characteristics in both boys and girls, the FDA said.

The two affected prescription medications are AndroGel 1%, made by Solvay Pharmaceuticals, and Testim 1%, made by Auxilium Pharmaceuticals. These are currently the only topical gel drugs approved by the FDA to address an insufficient or total lack of testosterone production among men.

Men typically rub the gels onto their upper arms or shoulders, according to the FDA.

According to the FDA, in 2007, pharmacies dispensed about 1.4 million prescriptions for the most popular medication, AndroGel, and about 370,000 prescriptions for Testim.

In addition to the new warning box, manufacturers will also have to develop a medication guide “to ensure that consumers who use these products are aware about the risk to children of secondary exposure,” Murphy said.

The new requirements arose after a thorough review of eight cases, reported since December 2008, in which children — ranging from as young as nine months to as old as five years — experienced a range of adverse side effects as a result of coming into direct and repeated contact with the treated skin of an adult user of either gel.

This type of exposure triggered “inappropriate virilization” among the young patients, Murphy said, including the onset of premature male characteristics in boys and inappropriate male characteristics among girls. The effects included “inappropriate enlargement of the penis or clitoris, premature development of pubic hair, advanced bone age, increased libido, and aggressive behavior” among the eight cases analyzed, Murphy said.

In most cases, these side effects subsided after exposure ceased, the FDA said, but in certain instances, genitalia enlargement and bone age did not revert to normal. As well, some children had to undergo invasive diagnostic procedures, while in one of the eight cases, hospitalization and surgical intervention was required.

“In the cases we reviewed, the average duration of exposure was around six months to a year” before the children received medical attention, noted Dr. Mary Roberts, a medical officer in the division of metabolism and endocrinology within the FDA’s Office of New Drugs, Center for Drug Evaluation and Research (CDER). “We can’t tell you if it lasted for five minutes or five hours, but we do know the exposure did occur over a period of time.”

Murphy and her colleagues hope the new labeling requirement will encourage consumers to more closely follow the approved protocol for the use of such gels. These include avoiding application of the drugs to parts of the body not indicated as appropriate; washing hands with soap and water after every application; and covering the application site with clothing once dry.

And they added that women should not use either gel, despite the fact the agency found that about 25,000 of the AndroGel prescriptions in 2007 were, in fact, dispensed to women.

More information

There’s more on testosterone replacement therapy at the U.S. Food and Drug Administration.

SOURCES: May 7, 2009, press teleconference with: Dianne Murphy, director, Office of Pediatric Therapeutics, Office of the Commissioner, U.S. Food and Drug Administration; and Mary Roberts, M.D., medical officer, division of metabolism and endocrinology, Office of New Drugs, Center for Drug Evaluation and Research (CDER), FDA

By Alan Mozes
HealthDay Reporter