Rhinorrhea, commonly known as a runny nose, is a symptom of the common cold and may also result from allergies (hay fever). The term comes from the Greek words "rhinos" meaning "of the nose" and "rhoia" meaning "a flowing."

Can also be a sign of withdrawal, such as from opioids. Kneisl, Wilson, & Trigoboff. (2004). Contemporary Psychiatric-Mental HEalth Nursing. Upper Saddle River, New Jersey: Pearson. pg274

Symptoms display circadian rhythms. Smolensky MH, Reinberg A, Labrecque G. (1995). Twenty-four hour pattern in symptom intensity of viral and allergic rhinitis: treatment implications. J Allergy Clin Immunol. 1995 May;95(5 Pt 2):1084-96.

See also: Rhinitis

References