A stuffy nose, medically known as nasal congestion, is the sensation of blockage or difficulty breathing through the nasal passages. This common experience arises when the tissues lining the nose become swollen, making it hard for air to pass. This article explains the internal changes that cause a stuffy nose.
The Healthy Interior of Your Nose
The inside of a healthy nose prepares the air we breathe before it reaches the lungs. The nasal septum, a wall of bone and cartilage, divides the nasal cavity into two passages. Three pairs of curved bony structures called turbinates, also known as conchae, extend from the side walls. These turbinates, covered by a moist mucous membrane, play a role in filtering, warming, and humidifying incoming air.
The mucous membranes lining the nasal passages are rich with small blood vessels and contain tiny hair-like structures called cilia. Cilia trap particles and move mucus, preventing foreign substances from entering the respiratory system. This structure ensures the air reaching your lungs is clean, warm, and adequately moisturized.
What Happens Inside During Congestion
When nasal congestion develops, the nose’s internal appearance changes from its healthy state. The most noticeable change is the swelling of the mucous membranes and turbinates. This swelling occurs because small blood vessels within these tissues become engorged, filling with extra fluid.
As tissues swell and blood vessels expand, nasal passages narrow significantly. This reduction in space makes it challenging for air to flow freely, causing the sensation of being “stuffed up.” Swelling is often accompanied by an increase in thicker mucus production. This combination of swollen tissues and excess mucus blocks the nasal airways, causing difficulty breathing through the nose.
Why Your Nose Becomes Stuffy
Internal changes leading to a stuffy nose are triggered by the body’s response to irritants or infections. A common cause is inflammation from illnesses like the common cold or flu, as viruses attack the nasal lining. Viruses activate the immune system, leading to nasal tissue swelling.
Allergic reactions also frequently cause congestion. When allergens like pollen, dust mites, or pet dander are inhaled, the immune system releases chemicals that cause inflammation and swelling in the nasal passages. Environmental irritants like smoke, strong odors, or sudden weather changes can also cause the nasal lining to swell. These triggers result in the symptoms of a stuffy nose.