Stuffiness is caused by excess mucus blocking the nasal passageways. Another culprit is swollen and/or inflamed blood vessels inside the nasal passages. Both of these issues can be worse at night.
Nighttime congestion is sometimes a matter of human anatomy and gravity. With some health conditions, lying down makes symptoms worse. Many people notice that congestion starts to improve an hour or two after they get up in the morning. That’s often gravity doing its work once again.
Anatomy and Congestion
When you are standing or sitting upright during the day, mucus is constantly draining naturally due to the force of gravity. It makes its way from your nose and sinuses into the back of your throat, where it is swallowed. You likely don’t even notice it’s happening.
However, when you are in bed or reclining in a horizontal position, gravity can cause mucus to pool or back up instead of drain.1
ny people find that one nostril is clogged at certain times of the day, but the congestion switches sides at night.
If only one nostril is clogged at night, it is likely due to alternate-side nasal congestion. This is due to a normal process known as the nasal cycle. The reason for the cycle is unknown, but it is not a disorder.2
The congestion occurs when a turbinate (a structure along the sinus wall that produces mucus) becomes swollen in one nostril. This blocks airflow on that side.
Gastroesophageal reflux disease (GERD) is a condition that causes stomach acid to flow back up into the esophagus, the tube that connects your mouth to your stomach.
Known as reflux, it occurs when the sphincter between the stomach and esophagus (esophageal sphincter) is weak and unable to stay closed. Acid reflux can cause nasal irritation that can lead to congestion.
People with GERD can experience acid reflux at any time of day. And hen you lie down and lose the help of gravity, stomach acid is even more likely to come up the esophagus.
This is why GERD symptoms, including nasal congestion, sore throat, coughing, postnasal drip, wheezing, and hoarseness, tend to be worse at night and first thing in the morning.