Coughing up phlegm with brown spots can be worrisome, especially for people living with lung cancer. If you have lung cancer and notice any changes in your symptoms, let your doctor know right away, especially if you see anything unusual in the color of your phlegm. In most cases, coughing up phlegm with brown spots is a sign of something other than lung cancer.

Understanding Phlegm

Phlegm is thick mucus produced in the lungs and can sometimes build up due to lung infection, allergies, asthma, irritants, or lung disease. Phlegm is also known as sputum. Your body produces mucus and phlegm to protect your intestines, mouth, sinuses, and airways.

Mucus keeps wet membranes — known as mucus membranes — healthy and helps protect them from disease-causing bacteria, viruses, fungi, allergens, and pollutants. If you are dehydrated or spend time in a dry environment, your body may produce extra phlegm to help keep the respiratory tract moist. Phlegm or mucus production can also increase when the immune system fights a potential threat.

What Do Different Colors of Phlegm Mean?

Healthy mucus or phlegm is clear or white, but any ongoing buildup of phlegm in the airways may be a sign of a health problem. If you cough up different colors of phlegm, it may be a sign of infection, disease, or exposure to toxic substances.

Excessive phlegm or color changes in phlegm to be aware of include the following:

• Clear phlegm can be a sign of viral pneumonia or viral bronchitis.
• White phlegm, though usually not serious, may be a sign of chronic obstructive pulmonary disease (COPD), gastroesophageal reflux disease (GERD, also called acid reflux), or congestive heart failure.
• Yellow or green phlegm is a sign of viral infection or bacterial infection such as pneumonia.
• Brown phlegm, a sign of old blood, can be a sign of infection, cystic fibrosis, inhaled pollutants, lung abscess, or an early sign of lung cancer.
• Black phlegm can be caused by smoking, pollutants, or fungal infection.
• Bloody phlegm, red phlegm, or pink phlegm can indicate a serious health condition such as pulmonary embolism, tuberculosis, or lung cancer.

Coughing up Blood May Be a Medical Emergency

Coughing up blood with lung cancer can be a sign of a life-threatening medical emergency known as a massive hemoptysis. It’s very important to recognize that fresh blood is bright red, rather than brown, and indicates recent bleeding that may be serious. Contact your doctor immediately or seek emergency medical care if you’re coughing up blood.

Other medical emergencies with lung cancer include obstruction of the central airway and massive pleural effusion in which fluid builds up in the tissues outside of the lungs. Both of these can make breathing very difficult.

Phlegm With Brown Spots

If you have lung cancer, coughing up phlegm with brown or rust-colored spots or specks may indicate old blood or may be caused by inhaled pollutants.

Common causes of brown spots in phlegm include:

• Tobacco smoke or exposure to secondhand smoke
• Dirt, dust, air pollution, chemicals, or metals in environmental or occupational settings
• Some medications
• GERD
• Infection
• In rare cases, food or beverages that may have been inhaled

You may see spots of old blood in phlegm if you’ve had blood in your lungs at some point during your lung cancer journey. Another health condition or lung irritation could also have caused bleeding in the airways, which may also result in traces of old blood.

Let your oncologist or pulmonologist know if you see brown spots in the phlegm you have coughed up. Although brown spots in phlegm with lung cancer are often not considered a serious problem, your doctor will still want to check them out. They’ll make sure these spots aren’t a sign of another problem that might need different treatment.

One MyLungCancerTeam member asked if their symptoms might be due to lung cancer: “I have shoulder and rib pain and am coughing constantly with some brown phlegm coming up. Are those symptoms?”

Coughing up phlegm that is brown or that contains brown spots may be a warning sign of undiagnosed lung cancer. This is especially true if it accompanies other common symptoms of lung cancer, such as:

• Persistent cough
• Fatigue
• Chest pain
• Loss of appetite
• Unexplained weight loss
• Shortness of breath or difficulty breathing
• Hoarseness

Managing Phlegm With Brown Spots

Always talk to your doctor about any ongoing or changing symptoms, such as coughing up phlegm with brown spots. A chronic cough can affect your quality of life, and your doctor can advise you how best to manage your cough with phlegm. Your doctor may encourage you to cough up the phlegm in your lungs or may have recommendations for relieving your cough.

Sometimes, your doctor may recommend treatment options such as a prescription or over-the-counter medication to help loosen phlegm and manage your cough. Some tips for coughing up phlegm that you can discuss further with your doctor include:

• Using a humidifier so that air stays moist
• Drinking plenty of water to keep hydrated
• Gargling with saltwater
• Applying topical eucalyptus oil ointments
• Sitting upright while coughing
• Practicing deep breathing to control coughing

If you or someone you love has lung cancer and starts coughing up phlegm with brown spots, it’s essential to let your doctor know. While it might not be a major issue, those brown spots could be a sign of old blood or an infection. Keeping in touch with your doctor about new symptoms is crucial for managing lung cancer and staying as healthy as possible.

Talk With Others Who Understand

MyLungCancerTeam is the social network for people with lung cancer and their loved ones. More than 12,000 members come together to ask questions, give advice, and share their stories with others who understand life with lung cancer.

Have you coughed up phlegm with brown spots? Was your phlegm with brown spots due to a cause other than lung cancer? Share your experience in the comments below, or start a conversation by posting on your Activities page.