Nasal drainage isn’t exactly anyone’s favorite topic—but it’s one of your body’s most important first lines of defense. That runny nose or post-nasal drip isn’t just an annoying symptom; it can reveal a lot about what’s going on with your health.

“Mucus may seem minor, but it’s one of the most important indicators we have when something’s not quite right in the nose and sinuses,” Dr. Arjuna Kuperan explains. “Paying attention to it can often catch an issue before it becomes something bigger.”

As one of Texas’s few fellowship-certified nose and sinus specialists, Dr. Kuperan sees patients every day with questions about their mucus. Is it normal? Is it a sign of infection? Should I be worried? Understanding what mucus is, and what its color might be telling you, is the first step toward breathing easier.

What Is Mucus and Why Does It Change Color?

Your nose and sinuses are lined with mucous membranes that produce mucus, a protective coating to keep your airways moist, trap irritants, and defend against infection. It might not look glamorous, but mucus does a lot behind the scenes.

Mucus contains:

• Antibodies that help your immune system recognize and attack harmful invaders
• Enzymes that break down viruses and bacteria
• Water and proteins that keep your nasal passages hydrated

When something disrupts this balance—like a sinus infection, allergy, or environmental irritant—your mucus can change in both consistency and color.

Decoding Mucus Colors: When to Be Concerned

Clear Mucus

• What it means: Normal and healthy.
• Common causes: Allergies, mild irritation, or the early stages of a cold.
• Should you worry? Not usually. If symptoms linger, consider allergy testing or evaluation for chronic rhinitis.

White Mucus

• What it means: Congestion is beginning.
• Common causes: Early-stage viral infections or nasal inflammation.
• Should you worry? Not unless symptoms worsen or last more than 10 days.

Yellow or Green Mucus

• What it means: Your immune system is in action.
• Common causes: Bacterial or viral infection. The color comes from white blood cells (neutrophils) that release green-colored enzymes.
• Should you worry? If symptoms like facial pain, pressure, or thick drainage persist, it may be sinusitis and worth seeing a doctor.

Brown or Bloody Mucus

• What it means: Blood mixed with mucus.
• Common causes: Dried or irritated nasal tissue from excessive blowing, trauma, or even intranasal drug use.
• Should you worry? A small amount of blood isn’t usually serious. However, persistent or heavy bleeding could signal nasal polyps, chronic infection, or, in rare cases, tumors. It’s worth getting checked.

When Do You Need Antibiotics for Nasal Drainage?

Not all infections are created equal—and not all need antibiotics. Many cases of discolored mucus are due to viral infections, which clear up on their own. Antibiotics are only effective against bacterial infections.

Bacterial vs. Viral Infections

• Viral infections: Most common colds and flus fall into this category and usually resolve without antibiotics.
• Bacterial infections: These may require prescription treatment, especially if they don’t improve or worsen over time.

Signs You Might Need Antibiotics

Dr. Kuperan recommends watching for the following signs:

• Sinus pain or pressure with thick yellow-green mucus lasting longer than 10 days
• Fever, facial swelling, or symptoms that initially improve but then worsen
• Cough with persistent, discolored mucus
• Headaches or fatigue that don’t improve with over-the-counter care

Other Causes of Discolored Mucus

Not every case of thick or discolored mucus points to infection. A few other common culprits:

Allergies & Environmental Irritants

Pollen, dust, pet dander, smoke, or pollution can trigger your body to produce extra mucus—usually clear. Chronic allergies may lead to ongoing nasal congestion or thicker secretions.

Nasal Polyps & Chronic Sinusitis

These non-cancerous growths inside the nose can block normal drainage and lead to chronic congestion, pressure, and frequent infections.

Nasal Trauma & Intranasal Drug Use

Frequent nose blowing, picking, or use of nasal sprays and drugs can damage the sensitive lining of the nose, causing irritation and bleeding.

When to See a Doctor About Nasal Drainage

If your symptoms are lingering or worsening, don’t wait it out. Schedule an appointment if:

• Your drainage lasts more than 10 days
• Mucus is thick, foul-smelling, or persistent
• You experience facial pain, fever, or recurring headaches
• You notice a significant amount of blood in your mucus

Get Expert Care for Persistent Sinus Issues

Dr. Arjuna Kuperan believes healing begins with truly listening to your symptoms—and your story. If you’re struggling with frequent sinus infections, unexplained nasal symptoms, or drainage that won’t cease, it’s time to get answers.

“You don’t have to live with chronic sinus issues,” Dr. Kuperan says. “With the right diagnosis and treatment plan, we can help you breathe—and feel—better every day.”

As a fellowship-trained sinus specialist and one of Houston’s most trusted sinus experts, Dr. Kuperan offers advanced diagnostic tools and personalized care. Whether it’s a simple concern or a complex condition, he’s here to help.

Schedule your consultation with Dr. Kuperan today and take the first step toward lasting relief.