Vicks VapoRub, the popular menthol compound used to relieve symptoms of cough and congestion, may create respiratory distress in infants and small kids, according to a new study.
The study, by researchers at Wake Forest University Baptist Medical Center, has revealed that such products may stimulate mucus production and airway inflammation, which can have severe effects on breathing infants or young children because of the small size of their airways.
"The ingredients in Vicks can be irritants, causing the body to produce more mucus to protect the airway," said Bruce K Rubin, MD, lead author of the study and a professor in the department of pediatrics at Brenner Children's Hospital, part of Wake Forest Baptist.
"Infants and young children have airways that are much narrower than those of adults, so any increase in mucus or inflammation can narrow them more severely," Rubin added.
Rubin and colleagues' interest in the study developed when they treated an infant who was taken to the emergency room after developing severe respiratory distress following the application of Vicks directly under her nose.
Researchers sought to determine the effect of the product on the respiratory system using ferrets, which have an airway anatomy and cellular composition similar to humans.
The team conducted tests on healthy ferrets and ferrets that had tracheal inflammation (simulating a person with a chest infection) that measured the effects of Vicks on mucus secretion and buildup in the airways, and fluid buildup in the lungs.
The researchers found that Vicks exposure increased mucus secretion in both normal and inflamed airways. Also, the studies showed that exposure to the product decreased the rate by which mucus was cleared from the trachea.
The findings support current product labelling, which indicates the product should not be used on children under two years of age. The study appears in this month's issue of Chest.