Soothing vapors inhaled into the nose and throat relieve nasal congestion and coughs due to colds. VapoRub is applied externally to the chest or throat, so it doesn't interact with other medication the way pills can, and is not likely to cause drowsiness or jittery side effects. VapoRub may be an alternative to oral decongestants for people who suffer from hypertension, and may be suited for diabetics who are looking for a sugar-free cough suppressant. Vicks VapoRub may also be rubbed on sore muscles to relieve aches and pains.