I’m not thoroughly convinced that the smelly stuff in the blue jar is dangerous, even though ferrets have trouble with it. In a recent small study, ferrets developed respiratory distress after Vicks VapoRub, which contains menthol, was rubbed under their nose.

Does this translate to children? Scientists studied the furry critters based on a single case report on one sick child whose condition seemingly worsened after her grandmother rubbed it around her nose. The product clearly states that it’s not for use in children less than two years old. 

Concerned parents who need a decongestant for their very young children should use a cool-mist humidifier and nasal suction bulbs. Salt water nasal sprays like Ayr or Ocean Saline are fine too.