Many parents slather Vicks VapoRub on their sniffling, coughing kids when they're sick -- because, by gosh, that's what their parents did to them. For children under the age of 2, the folksy remedy could be dangerous, researchers warned today.
Reporting in Chest, the journal of the American College of Chest Physicians, the researchers said that using the ointment to ease coughing and congestion in children of this age might lead to severe breathing problems by increasing mucus production and inflammation.
The product's label cautions against using Vicks VapoRub on children under 2, but many parents do so anyway, putting their infants at risk, experts said.
"People don't read warnings on prescription medications, so to [read a warning for] a salve on the outside of the body that has been around for 100 years . . . I think it would be a rare parent who would do that," said lead author Dr. Bruce K. Rubin of Wake Forest University Baptist Medical Center in Winston-Salem, N.C.
Vicks VapoRub, whose active ingredients are camphor, menthol and eucalyptus oil, was first formulated in 1891 in Greensboro, N.C. National marketing began in 1905, and it gained great popularity during the Spanish flu epidemic of 1918.
Several small studies have failed to show any medicinal benefit from the ointment, Rubin said. He suspects that the menthol in it binds to cold receptors in the throat, giving the impression that the patient is breathing more easily even when that is not the case.
The ointment's risks came to the attention of Rubin and his colleagues when they treated an otherwise healthy 18-month-old girl who was brought to the emergency room by her grandparents after her respiratory infection suddenly grew worse. Questioning revealed that the severe symptoms appeared shortly after they had put Vicks VapoRub under her nose.
The researchers were already using ferrets -- whose airway anatomy and cell lining are similar to humans -- to study infant respiratory problems. To look at the effect of Vicks, they applied the ointment directly to cultured ferret tracheal cells as well as under the noses of healthy ferrets and ferrets with tracheal inflammation similar to that of humans with a cold.
In the cultured cells, the ointment increased mucus secretion by 59%. It increased secretion by 14% in the airways of healthy animals and by 8% in those with inflamed airways.
Because the airways of infants are much narrower than those of adults, "any increase in mucus or inflammation can narrow them more severely," Rubin said.
The ointment also slowed the action of the hair-like cilia in the throat that carry mucus away.
The team has since identified three more infants brought to emergency rooms with breathing problems after receiving Vicks VapoRub. All four recovered quickly once application of the ointment was stopped.
David Bernens, a spokesman for Vicks VapoRub manufacturer Procter & Gamble Co., said, "The safety and efficacy of the product has been determined by multiple clinical trials with over 1,000 children tested. . . . Our results are inconsistent with the claims of this study."
Bernens added that the company's post-marketing surveillance shows only three adverse incidents per 100 million units sold, with no mention of respiratory distress among them.
Conscientious pediatricians would not recommend that parents use Vicks VapoRub "because it hasn't been shown to be effective," said Dr. Daniel Craven, a pediatric pulmonologist at Rainbow Babies & Children's Hospital in Cleveland who was not involved in the study. However, he added, "we were never concerned that it would cause a problem."
Craven argues that the new study is too small to confirm the risk from the ointment. He said he hoped "some more studies will be undertaken to further support or refute the possibility."
The report comes when pediatricians and health authorities have already been warning parents about the risks of using cough syrups and decongestants in infants and young children.
"The bottom line is, none of them have been proven by research to work" and there are risks involved, Craven said. "There are no miracle cures for a respiratory virus infection."
The body has evolved ways to fight such infections, Rubin said -- strategies that include coughs, sneezes and mucus that traps microbes and moves them away from the throat.
"All of those are great things," he said. "To help the body's defenses, the best things are love and hugs, warm liquids like chicken soup, and time."