(HealthDay News) -- Nasal congestion, commonly called a stuffy nose, occurs when the tissues that line the inside of the nose become swollen.

The U.S. National Library of Medicine says common causes of nasal congestion include:

• Having the common cold or flu.
• Having a sinus infection.
• Having allergies.
• Using nasal sprays or drops for longer than three days.
• Having nasal polyps.
• Being pregnant.
• Having a condition called vasomotor rhinitis.