Phlegm is something that bothers many people, both during and after the weather changes. Its symptoms include chronic coughing, shortness of breath, and a constant state of phlegm in the throat. Here are the main causes of phlegm:
Bacterial and viral infections: When you have a respiratory infection like a cold, flu, bronchitis, or pneumonia, the body produces more phlegm to fight it off. This phlegm builds up in the chest and airways, which turns into phlegm.
Sinusitis: Due to an infection in the sinus cavities in the forehead and cheeks, phlegm drains down the back of the nose into the throat (Post-nasal drip). This is what causes severe phlegm and a sore throat in many people when they wake up in the morning.
Allergies and air pollution: Inhaling dust, smoke, pollen, and pet dander can cause the airways to swell and increase the amount of phlegm. Smokers and those who are close to smokers (passive smoking) often have persistent phlegm.
Respiratory diseases like asthma: People with chronic diseases like asthma or COPD have their airways constantly constricted. Even a mild allergy can cause thick mucus to form in their body and cause difficulty breathing.
Gas problems and acidity (GERD): This is a cause that many people don’t realize. In a condition where stomach acid comes up into the throat (Gastroesophageal Reflux Disease), the acid irritates the airways, and to combat this, more mucus is produced in the throat and chest.