Mucus isn't exactly something people give much thought to — until they're sick and dealing with a constantly runny nose. But mucus is actually an important part of a healthy immune system, according ...

Medically reviewed by Susan Russell, MD Key Takeaways Coughing up white mucus can be a sign of an upper respiratory infection or chronic conditions like COPD. Viral infections that cause white mucus ...

Healthy phlegm is usually clear and runny, but many different health conditions can change the consistency or color. Phlegm, also called sputum, is mucus produced by your lungs that helps protect your ...

Coughing is a natural reflex for clearing the throat and lungs of irritants. Infection is a common cause of a dry cough. Other possible causes include postnasal drip, asthma, idiopathic pulmonary ...

Bloody boogers form when blood mixes with mucus in the nose and the mucus dries. Various causes may include nose-picking or ruptured vessels. The nose lining is delicate and rich in blood vessels, and ...

A dry cough causes a scratchy throat but doesn't produce mucus. Upper respiratory infections, allergies, and asthma often trigger it. Illnesses like the common cold, COVID, and the flu often cause dry ...

Hard boogers in the nose can be helpful in keeping dirt and germs out of your airways, but bloody boogers could indicate irritation or infection. If this is the case, a doctor can treat any underlying ...

Cystic fibrosis (CF) is a genetic disorder that causes severe lung damage and nutritional problems in children. Years ago children with the disease were not expected to survive beyond their teens, but ...