Vicks VapoRub can sometimes cause breathing problems in infants.
Vicks VapoRub can cause respiratory distress in children under 2 when inappropriately applied directly under the nose, U.S. researchers have said.
They said using the Procter & Gamble Co (PG.N) product in this way can cause a young child's tiny airways to swell and fill with mucus, triggering severe breathing problems.
"The only problem we've seen is in a small child when it has been put under the nose," Dr. Bruce Rubin of Wake Forest University School of Medicine in North Carolina, said in a telephone interview.
Rubin said the ingredients in Vicks can be irritants, causing the body to produce more mucus to protect the airway. And since infants and young children have airways that are much narrower than those of an adult, any increase in mucus or swelling can narrow them severely.
"The company is really clear it should never go under the nose or in the nose for anybody and it shouldn't be used in children under 2," said Rubin, whose study appears in the journal Chest.
While the researchers only tested the Vicks product, Rubin said similar products, including generic versions, could cause the same negative effects in infants and toddlers.
Rubin and his colleagues began looking at use of the medication after treating an 18-month-old girl who developed respiratory distress after the salve was put under her nose.
They studied ferrets, which have an airway anatomy similar to humans. In the animals with a chest infection, the product increased mucus secretion and decreased the animal's ability to clear mucus.
"We were able to document changes that we think explain this," Rubin said.
David Bernens, a spokesman for P&G, said the finding came as a surprise. "Vicks VapoRub has been proven safe and effective through multiple clinical trials. It has been in the market for over 100 years," Bernens said, noting that the label says the product should not be used in children under age 2 without a doctor's advice, and not under the nose.
"We warn people not to do that," he said.
Since the initial episode, emergency doctors at the medical center have begun asking all parents of children in respiratory distress if they used the Vicks product in a similar way and they have seen two more cases, Rubin said.
"I recommend never putting Vicks in, or under, the nose of anybody -- adult or child," Rubin said in a statement, adding that he would never use it in a child under age 2.
Dr. James Mathers, president of the American College of Chest Physicians, said in a statement that parents should consult their doctor before giving any over-the-counter medication to infants and young children, particularly cough and cold medications, which can be harmful.Have you used Vicks on a baby? Did it help or make things worse?