Post-Nasal Drip

What Does It Mean When You’re Coughing Up Brown Mucus?

February 7, 2024

7 minutes

Reviewed by Michael Kaplan, MD

Coughing up brown mucus can be an unsettling experience, often leaving you feeling uneasy and concerned about your health. This common symptom is typically a sign that your body is fighting to expel irritants or infections present in the respiratory system. 

So, what does it mean when you cough up brown mucus? Brown mucus can arise from a variety of causes, some benign and others requiring medical attention, including:

  1. Smoking
  2. Air pollution
  3. Occupational toxins
  4. Respiratory infections like bronchitis or pneumonia
  5. Chronic lung conditions such as COPD

In this blog, the sinus experts from Kaplan Sinus Relief explore the common causes behind this unsettling symptom and offer advice on when to seek medical attention.

1. Smoking

Smoking is a well-known cause of dark brown mucus for both occasional and long-term smokers. This is because tobacco smoke contains harmful substances that can irritate the respiratory system, causing it to produce excess mucus as a defense mechanism. Over time, constant exposure to these irritants can lead to chronic bronchitis, which often manifests as a persistent cough and brown mucus.

Other symptoms of chronic bronchitis include:

  • Wheezing
  • Shortness of breath
  • Chest congestion

If you’re a smoker and are experiencing brown mucus, it may be time to consider quitting to improve your respiratory health. However, you can also experience brown mucus from secondhand smoke, so it’s important to limit your exposure to smokers in your environment.

2. Air pollution

Inhaling pollutants present in the air, such as dust, smog, or smoke from nearby fires, can also cause your body to produce brown mucus in the throat. Similar to smoking, these irritants can trigger an inflammatory response in the respiratory system, leading to excess mucus production, a cough, and even strange-smelling mucus if the pollutants become trapped in your nose.

If you suspect that air pollution is the cause of your brown mucus, you can use at-home remedies such as:

  • Steam inhalation to help loosen the mucus and expel it from your system
  • Saline nasal irrigation to flush out any irritants from your nasal passages
  • Staying hydrated to thin out the mucus and make it easier to expel

To minimize exposure to air pollution, consider wearing a mask when going outside or investing in an air purifier for your home. Additionally, try to stay indoors during times of high air pollution, such as on smoggy days. If your symptoms persist or worsen, it’s important to consult a doctor for further evaluation and treatment.

3. Occupational toxins

Those who work in environments with elevated levels of toxins may also experience brown mucus as a result of exposure. This includes people working in factories, construction sites, or with chemicals. Similar to air pollution, these substances can irritate the respiratory system and 

cause excess mucus production. Additional symptoms of toxin exposure include: 

  • Headaches
  • Eye irritation
  • Difficulty breathing

If you work in such an environment, it’s important to follow safety protocols and wear protective gear to minimize your exposure to toxins. If you notice persistent brown mucus and other respiratory symptoms, consult a doctor for a proper diagnosis and potential changes to your work environment.

4. Respiratory infections

Seeing dark brown in your mucus or yellow mucus can be a sign of an ongoing respiratory infection, such as bronchitis, pneumonia, or even chronic sinus infections. These infections often cause the mucus to become discolored as a result of white blood cells fighting off bacteria or viruses. If you have a sore throat with brown phlegm or are coughing up dark brown mucus coupled with other symptoms of infection including fever, fatigue, and body aches, it’s important to consult a doctor for proper diagnosis and treatment.

Depending on the cause of the infection, your doctor may prescribe antibiotics, rest, balloon sinuplasty for chronic sinus infections, and/or other treatments to help alleviate symptoms. If left untreated, respiratory infections can lead to more serious complications, so it’s important not to ignore persistent symptoms.

Learn more: What color is sinus infection mucus?

5. Chronic lung conditions

Chronic lung conditions are often caused by long-term exposure to irritants such as tobacco smoke or air pollution and can cause brown mucus. The most common chronic lung conditions include: 

  • Chronic obstructive pulmonary disease (COPD): COPD is a progressive disease that affects the lungs, making it difficult to breathe and resulting in a persistent cough with excessive mucus production.
  • Chronic bronchitis: As mentioned earlier, chronic bronchitis is a common cause of brown mucus in smokers and can also occur as a result of exposure to occupational toxins or air pollution.
  • Bronchiectasis: This condition involves the scarring and widening of the airways in the lungs, leading to persistent coughing and the production of large amounts of thick, discolored mucus.
  • Emphysema: This condition involves damage to the air sacs in the lungs, resulting in difficulty breathing and coughing up brown mucus.
  • Asthma: Asthma is a chronic respiratory condition that can cause inflammation and narrowing of the airways, leading to symptoms such as wheezing, chest tightness, and coughing with mucus production. In some cases, asthma can also cause brown mucus due to inflammation and irritation of the airways.

Common symptoms of chronic lung conditions include: 

  • Persistent cough with mucus
  • Shortness of breath
  • Chest tightness and discomfort

If you have a history of smoking or exposure to irritants and are experiencing brown mucus along with any of the symptoms listed above, it’s crucial to consult a doctor for diagnosis and treatment. Early detection and management can help slow the progression of the disease and improve your quality of life.

Treatment options may include quitting smoking, avoiding triggers such as air pollution or occupational toxins, and taking medication as prescribed. In some cases, surgery or other medical interventions may be necessary to improve breathing and reduce the production of brown mucus.

What causes the mucus to turn brown?

The distinctive brown color of the mucus is typically the result of the presence of tar, toxins, and other substances that are inhaled into the respiratory system. When you smoke, or when you are exposed to pollutants in the environment, these particles get trapped in the sticky mucus produced by the linings of your airways. The more prolonged or intense the exposure, the more stained the mucus can become, turning it from its normal clear or white appearance to varying shades of brown.

In the case of respiratory infections, the brown color can be attributed to dried blood residue from inflamed and irritated airways or the presence of certain types of bacteria or dead cells dislodged from the respiratory tract. It’s crucial to be aware that while occasionally coughing up brown mucus may not be a cause for immediate concern, if it persists, it could be an indication of a more serious underlying health condition that requires medical attention.

Is your brown or yellow mucus caused by chronic sinus infections? Kaplan Sinus Relief can help!

Coughing up brown mucus is a symptom that may arise from a variety of conditions, ranging from environmental irritants to chronic respiratory diseases, and warrants medical attention to determine its cause and appropriate treatment.

So, whether you’re coughing up brown mucus in the morning or throughout the day, it’s important to consult a medical professional to determine the underlying cause. At Kaplan Sinus Relief, we specialize in diagnosing and treating chronic sinus infections using advanced techniques such as balloon sinuplasty for drainage and cough, chronic sinus infections, and allergies.

Dr. Kaplan, one of the pioneers of the balloon sinuplasty procedure, can help you find relief from recurring respiratory symptoms and improve your overall quality of life. Contact us to schedule an appointment and take the first step towards better health today!

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