Breathe freely again by clearing blocked passageways and easing sinus pressure. Nasal congestion, also known as stuffy nose, is a symptom of another health problem, such as sinus infection, but it may also be caused by the common cold. It is characterized by a stuffy or runny nose, sinus pain, mucus buildup, and swollen nasal tissues. For long-term nasal congestion, a number of factors may be attributed to be the cause including allergies,hay fever, nasal polyps, chemical exposures, environmental irritants, and among many others. According to research or other evidence, the following self-care steps may be helpful.