where does phlegm come from
Phlegm is a mucus-like substance produced by the lower airways, such as the lungs and the respiratory system leading to the lungs, not by the nose and sinuses, which produce the mucus that streams out of or clogs up your nose. You may not notice phlegm unless you cough it up as a symptom of bronchitis or pneumonia.As is the case with mucus, phlegm that has a color such as green or yellow may indicate infection. Any time you see blood in the phlegm you cough up, you should seek medical attention. 3. Post-nasal drip (thick mucus). 2  Take an expectorant (this thins mucus and phlegm), drink lots of fluids, breathe through a warm washcloth, and use steam to make the mucus more liquid. 3  Congestion (blocked nose).