eli5 how does the nasal cycle work?

Question

I understand what it is, buy what is “blocking” the airway? Is the inside of your nose shrinking? I can’t find a straight answer.

In: 3

Answer 1

Your nose goes through a cycle, dude! Left nostril, right nostril, taking turns being blocked (not entirely, just around 70% or so). The septum swells on one side, reducing airflow. Then, it’s a tag team – the swelling subsides and the other nostril gets the ‘swell’ treatment. No shrinking, just good ol’ ebb and flow.