Eli5: what is the crackling sound you hear when you’re sick

Question

Lying here, trying to sleep and when I breathe out, there’s that bubbly, crackly sound that happens in your throat. What is that?

In: 2

Answer 1

A crackling sound can sometimes be heard from the lungs because they contain tiny sacks which normally fill with air in order to exchange gasses with our blood. If those sacks fill with fluid then as air enters it shifts the fluid around and forms air bubbles, all of which can result in a crackling sound.

This also means you have pneumonia.