during certain seasons or after exposure to a particular environment.
For example, you might feel worse when cleaning a dusty room or spending time around a particular animal.
Identifying and reducing exposure to triggers can be an important part of managing allergy-related mucus.
A Cold or Other Respiratory Infection May Be the Cause If your phlegm appeared relatively suddenly, an infection may be responsible.
Common respiratory infections can cause inflammation and increased mucus production.
You may also experience:
Cough
Sore throat
Runny nose
Nasal congestion
Fatigue
Headache
Mild fever or chills
During an infection, mucus can become thicker and may change color.
This is important because colored mucus does not automatically mean you have a bacterial infection.
White, yellow, or green mucus can occur as the immune system responds to an infection, including viral infections. Color alone generally cannot determine whether antibiotics are necessary.
Most uncomplicated viral respiratory infections improve
