A study comparing vapor rub, petroleum jelly or no treatment concluded that vapor rub is most effective in relieving symptoms of congestion and coughing, and making it easier for children and parents to sleep.

Vapor rub, which is a salve containing camphor, menthol and eucalyptus oil, provides children aged 2 and above with relief during periods of cough and cold illnesses.

"Our data suggests that the vapor rub provides systematic relief", said Ian M. Paul, MD, an associate professor of pediatrics and public health science at Penn State College of Medicine. Although there are no concrete figures, Mr. Paul reported that the difference between treatment outcomes was significant.

Although vapor rubs have been used for more than a century, studies on its effectiveness are limited, said Mr. Paul. He speculates that menthol improves the nasal sensation of air flow.

These findings are good news for parents of young children, who have few options when these illnesses strike. The FDA, supported by the American Academy of Pediatrics, announced in 2008 that children under 2 years should not be given cold medicines because of potentially dangerous side effects.

The study was funded through an unrestricted grant from Procter and Gamble, which makes Vicks VapoRub, the product used in the study. The researchers were permitted to publish results regardless of the outcome of the study.