Colds, flu, sinusitis, bronchitis, or viral/bacterial infections can cause phlegm to build up. The body produces more phlegm to fight the infection. Allergies: Dust, smoke, pollen, and pet dander in the air can irritate the airways and increase phlegm. Smoking: Smoking damages
lung cells and causes excessive phlegm production (Smoker’s cough). Air pollution: Smoke from vehicles and pollution from factories can irritate the lungs and lead to phlegm. Asthma: People with asthma may produce more phlegm due to inflammation in the airways. Gastroesophageal reflux (GERD):
Stomach acid refluxing back into the throat can cause a feeling of a lump in the throat.
Dry weather: When the humidity in the air decreases, the airways become dry and the body produces mucus to combat it.
