At night I usually have one nostril stuffed, blocked up, no air coming through. On top of this, I get post nasal drip from it, and it makes me choke. Often it keeps me up at night. It's not an infection. I don't feel sick. It goes away in the morning. When I use immune mist at night, the nasal passage clears right up. No more post nasal drip, and I sleep much better. Also, if I use immune mist when I think I'm getting a cold, it often stops it, especially if I also suck on a zinc lozenge.