Phlegm is the body’s natural way of combating a respiratory infection. It’s the mucus the lungs produce to help expel irritants, which come from an infection. It typically accompanies the flu and common cold.
In other words, when you’re suffering from an infection such as the flu, common cold or bronchitis, your body produces more phlegm to capture the inflammatory cells, virus, or bacteria that are triggering the damage.
The most common phlegm build up symptoms include weakness, feeling slightly feverish, constant need to clear your throat, persistent coughing, a runny nose, and difficulty breathing.
You should be able to cough phlegm out. But, some phlegm build up may seem persistent.Therefore, you should remove the phlegm from your body before it builds up too much