Phlegm is a protective secretion that the airways produce to expel germs and foreign particles. It increases during infections; children usually swallow phlegm rather than spitting it out — this is harmless and is eliminated in the stool.

Causes

  • The common cold and other viral upper respiratory tract infections (most common)
  • Bronchitis, bronchiolitis, pneumonia
  • Postnasal drip in allergic rhinitis (especially causes a morning cough)
  • Exposure to cigarette smoke

What Does the Color of Phlegm Tell Us?

Yellow-green phlegm on its own does not mean a bacterial infection or that antibiotics are needed; the color may darken during the recovery process. What matters is the course of the fever, the general condition, and whether the duration is becoming prolonged. Bloody phlegm, however, always requires an examination.

To Loosen Phlegm at Home

  • Plenty of fluids (water is the most natural expectorant)
  • Nasal rinsing and aspiration (in babies)
  • Humidifying the environment; a smoke-free home
  • For children over 1 year, half to one teaspoon of honey at night (honey is forbidden under 1 year of age)
  • Over-the-counter expectorants and cough syrups are not recommended under 6 years of age

When Should You See a Doctor?

A productive cough lasting more than 3 weeks, accompanied by high fever, rapid breathing, wheezing, or failure to gain weight must always be evaluated. A productive cough with abundant phlegm lasting for months calls for investigation of chronic conditions such as bronchiectasis.