Definition:

Phlegm is a thick, sticky fluid made by the lining of the respiratory tract, especially in the lungs and throat. It is a type of mucus, but not all mucus is phlegm.

What is phlegm?

• Phlegm is the thick, gooey stuff you feel in your throat or chest, especially when you’re sick.

• It’s made by your lungs and air tubes (airways) to trap bad things like germs, dust, or smoke.

• It’s different from normal mucus because it shows up when there’s a problem (like a cold or infection).

What Is It Made Of?

• Water: Phlegm is mostly water so it can move through your body.

• Sticky proteins (mucins): These make phlegm thick and help trap germs and dirt.

• White blood cells: These are the fighters that come when you’re sick. They help kill bacteria and viruses.

• Dead germs and dirt: Stuff your body is trying to clean out.

Why Do We Cough It Out?

• Your body doesn’t want phlegm to stay inside.

• Tiny hairs in your airways push the phlegm upward toward your throat.

• When there’s a lot of it, your body tells you to cough so you can spit it out or swallow it.

What Do the Colours Mean?

The color helps doctors guess what’s going on:

• Clear = normal or just allergies (no infection)

• White = a little sick, like a cold (mild swelling in your airways)

• Yellow = your body is fighting germs (you have white blood cells in the phlegm)

• Green = stronger infection, like from bacteria (more white blood cells)

• Brown = old blood, dirt, or smoke from your lungs

• Red or Pink = fresh blood (could be from too much coughing or something more serious)

When Do You Get Phlegm?

You usually get phlegm when your body is fighting or reacting to something:

• Colds or Flu: Virus infections make your body produce more mucus.

• Bronchitis: Infection in the tubes of your lungs. Makes thick phlegm.

• Pneumonia: Infection in the lungs. Can make yellow or green phlegm.

• Asthma: Even though it’s not an infection, your body can make thick mucus.

• Allergies or Dust: Your body reacts by making mucus to trap it.

• Smoking: Irritates your lungs and causes constant phlegm.

Favourite part/ note/ summary- Phlegm is not a disease or a condition, in fact it is the defence mechanism of our body. Phlegm is a thick and sticky fluid produced by the lining of the respiratory system. It’s made out of water, sticky proteins, White Blood Cells (WBC) and dead germs or dirt. It’s made out traps the pathogens, germs, dirt etc from entering our body. It can come in different colours like clear which means normal or just allergies, white means a slight cold, yellow means your body is fighting germs, brown means old blood or dirt, and finally pink or red means it’s fresh blood you either get it through, coughing too much with stress or other problems.