Mucus serves as a protective barrier within the respiratory system, lining the lungs, throat, mouth, sinuses, and nose. It traps inhaled particles like dust, allergens, and microorganisms. It also keeps airway tissues moist, preventing them from drying out. While typically clear, the color of mucus can change, offering clues about what is happening inside the body.
The Science Behind Snot Color
Mucus turns yellow or green due to the body’s immune response to an infection. When the immune system detects invaders, it dispatches white blood cells called neutrophils. Neutrophils are the most abundant type of white blood cell and act as a primary line of defense.
These neutrophils contain myeloperoxidase (MPO), an enzyme with a green pigment due to its iron content. As neutrophils fight off pathogens, they release MPO, and when these cells break down, the green pigment becomes more prominent in the mucus. The yellow or green hue indicates the presence of these immune cells and their enzymes, not necessarily a bacterial infection.
Common Conditions Causing Yellow-Green Snot
Yellow or green mucus often accompanies common respiratory illnesses. The common cold often begins with clear, watery mucus that later thickens and turns yellow or green as the body fights the viral infection.
Sinusitis, an inflammation or infection of the sinuses, often presents with thick, discolored mucus. Blocked nasal passages in sinusitis can lead to mucus buildup that turns yellow or green. Bronchitis, an inflammation of the bronchial tubes, can cause a cough that brings up yellow-green mucus. While these conditions can be caused by viruses, a prolonged presence of discolored mucus might sometimes indicate a secondary bacterial infection.
When to Consult a Doctor
While yellow or green mucus is often normal, certain signs warrant medical attention. Consult a healthcare provider if symptoms persist for more than 10 to 14 days without improvement, or if they worsen after initially feeling better. Seek medical advice for a high fever (above 102°F or 38.9°C), severe facial pain or pressure that worsens when bending over, or swelling around the eyes.
Also seek medical attention for difficulty breathing, shortness of breath, chest pain, or coughing up blood. These symptoms could indicate serious complications like pneumonia or a severe infection requiring specific treatment. Individuals with weakened immune systems or chronic health conditions should also contact a doctor if they develop discolored mucus and other concerning symptoms.
At-Home Remedies and Prevention
For typical cases of yellow or green mucus, several at-home remedies can help manage symptoms and promote recovery. Staying well-hydrated by drinking plenty of fluids, such as water, helps thin mucus, making it easier to clear from nasal passages and the throat. Using a humidifier in your living space adds moisture to the air, soothing irritated nasal passages and loosening congestion.
Saline nasal sprays or rinses can effectively clear mucus and reduce congestion. Over-the-counter pain relievers can alleviate discomfort like headaches and body aches. To prevent the spread of respiratory infections, frequent handwashing with soap and water, especially after coughing or sneezing, is important. Avoiding touching the face, covering coughs and sneezes, and staying home when sick also contribute to limiting germ transmission.