4. Postnasal drip
This is probably one of the most annoying symptoms of respiratory allergies because it is something we can do nothing about. Postnasal drip is a constant sensation of fluid dripping in the posterior part of the nose. It is caused by an overflow of nasal secretion that is not correctly eliminated by the nasal cavity and starts dripping toward the pharynx and other parts of the respiratory and digestive system. It is often associated with sneezing and the rest of the respiratory symptoms described in this article.