A runny or stuffy nose can be due to colds, allergies, sinus infections or the flu. When there is an excess of mucus secretions the nose is runny. The additional secretions drain from the front of the nose, or down the back (post-nasal drip). The sensation of a stuffy nose occurs when the membranes that line the nose become swollen from inflamed blood vessels.
Update Date 8/18/2013
Updated by: Linda J. Vorvick, MD, Medical Director and Director of Didactic Curriculum, MEDEX Northwest Division of Physician Assistant Studies, Department of Family Medicine, UW Medicine, School of Medicine, University of Washington. Also reviewed by David Zieve, MD, MHA, Bethanne Black, and the A.D.A.M. Editorial team.