A single clogged nostril can also be the result of a deviated septum, chronic inflammation, nasal polyp obstruction, alcohol consumption, or even sleeping on one’s side. “Side sleeping can definitely cause nasal congestion,” Dr. Anthony Cornetta, board-certified otolaryngologist at NYU Langone, told PopSugar. “The side down to the pillow will get more stuffy due to gravity.”
However, a one-sided clogged nose is usually at its worst when we’re sick. Whether it’s due to allergies or a cold virus, congestion can feel like it’s at an all-time high when we’re under the weather. Why is it that one of our nostrils always feels far more clogged than the other during these times? Essentially, all that back-and-forth blood flow between nostrils that’s part of the everyday nasal cycle gets kicked up a notch when we’re sick. With even more blood flow being sent to our nasal passages, we experience more swelling and mucus production than normal (per Men’s Health). Usually, the congestion is more noticeable in the nostril that’s already the focus of the nasal cycle at that moment. Once it switches, you’ll likely feel more congestion in the opposite nostril.