Why Are You Coughing Up Black Mucus or Phlegm?

Key takeaways:

• Coughing up black mucus or phlegm may be caused by smoking; vaping; or exposure to smoke, toxins, dust, coal, and industrial chemicals.
• Lung or sinus infections, especially those caused by fungi, can cause you to cough up black mucus or phlegm.
• Coughing up black mucus or phlegm could be a warning sign; seek medical attention promptly due to the risk of internal bleeding or cancer.

Black mucus or phlegm can develop after inhaling smoke or other harmful pollutants. This is most common among smokers or those who are exposed to secondhand smoke. When coughing, they may notice a black or gray-colored mucus. Even being near a campfire can irritate the vocal cords and lungs, and this can lead to coughing up black mucus or phlegm. Coal workers or those in dusty environments, such as automobile repair shops or manufacturing facilities, may also experience this issue.

Coughing up black mucus or phlegm could indicate an unusual type of infection. Some infections caused by fungi, for instance, may result in coughing up black mucus or phlegm. These fungal infections can affect the nose, sinuses, airways, or lungs. They typically affect individuals with weakened immune systems or those who live in specific regions of the world.

Lastly, coughing up black mucus may also indicate bleeding in the airways, which can stem from various causes. These include vigorous coughing, autoimmune diseases, or the use of blood thinners, such as those prescribed for rheumatoid arthritis.

Is coughing up black mucus or phlegm normal?

First, it’s important to understand what mucus and phlegm are. Mucus is a thin, slippery liquid that plays a vital role in the immune system. It provides essential lubrication to airways, helping to keep them healthy. Mucus is usually clear, whereas phlegm (a thicker type of mucus produced in the lungs), is normally a whitish color. It’s normal to cough up mucus or phlegm – but when it’s black, that isn’t necessarily normal.

If you’ve been coughing up black mucus or phlegm, it could result from exposure to smoke, soot, or dirt. Also, if you’ve been coughing intensely or feel as though you have an infection, you might notice traces of black and red in the mucus. In either case, it would be a good idea to consult with your doctor.

Causes of coughing up black mucus

When you cough up mucus or phlegm and notice that it’s gray or black, there could be several likely causes. These range from smoking and breathing in pollutants from the air to lung diseases and cancer.

Smoking, chemicals, and environmental pollutants

Smoking – whether from your own cigarettes or frequent exposure to secondhand smoke – is one of the most common causes of coughing up black mucus. Additionally, various chemicals and environmental pollutants can also contribute to this symptom. These may include:

• Industrial chemicals (which can cause bronchitis):
  • Asbestos
  • Coal
  • Cotton
  • Flax
  • Latex
  • Metals
  • Silica
  • Talc
  • Toluene diisocyanate
  • Western red cedar (dust)
• Areas with high levels of smoke from forest fires, volcanos, or air pollution

Note: Many people who remove themselves from polluted environments find that coughing up black mucus disappears quickly.

Infections

Coughing up black mucus may result from an infection of the sinuses, airways, or lungs. You may have vigorous coughing, and the black mucus may be from the infection itself or mild bleeding (causing red or black streaks). Infections that can cause you to cough up black mucus include:

• Bronchitis
• Sinusitis
• Pneumonia
• Tuberculosis

Coughing up black mucus can result from severe fungal infections in the sinuses or lungs, such as mucormycosis (although it is quite rare).

Lung conditions, heart disease, or taking blood thinners

Several lung conditions can lead to coughing up black mucus, including:

• Black lung disease from exposure to coal and coal dust;
• Pneumoconiosis: Any lung disease caused by the inhalation of organic or nonorganic dust and fibers, usually in an occupational setting;
• Bronchiectasis: A condition in which the airways become permanently widened and damaged (unlike bronchitis, which is temporary);
• Autoimmune disorders
  • Sarcodoidis
  • Rheumatoid arthritis
  • Systemic lupus erythematosus
• Heart valve disease
• Taking blood thinners, as they can cause internal bleeding

Lung or airway cancer

Persistent coughing up of black mucus could indicate a serious underlying condition, such as cancer. In that case, the black mucus results from dying cells or tissue, bleeding, or trapped debris and scar tissue. Persistent, deep coughing up of black mucus is typically accompanied by other signs and symptoms, like significant weight loss, fatigue, and possibly coughing up blood.

Other causes of coughing up black mucus based on the mucus’s appearance (or other symptoms/situations)

You may also cough up black mucus in other instances. These may be related to the time of day, occasional nasal dryness, allergies, or smoking.

Coughing up black-speckled mucus

When you cough up mucus with black specks, there could be various reasons for it, including:

• Inhaling pollution, dust, grime, or coal;
• Fungal infection, particularly in the nose or sinuses
• Nose bleeding or crusting in the nose from dryness

Coughing up black mucus in the morning only

Black mucus in the morning may occur due to dryness or bleeding from your nose while you sleep. If it disappears during the day, it may not be a cause for concern.

Coughing up black mucus after quitting smoking

After giving up smoking (congratulations to you!), you may have a temporary increase in coughing up black mucus. That’s because your lungs and airways are actively working to remove the tars and toxins that have accumulated from cigarette smoke. This coughing spree is usually temporary, lasting for just a few weeks. In some cases, however, it can persist for up to a year as your lung’s cells and tissues recover.

Diagnosing the reason(s) for coughing up black mucus

Your doctor will ask you a series of questions about the timing, amount, and frequency of your cough that produces black mucus. You’ll need to provide details about any potential exposure to smoke, chemicals, or other hazardous substances. After that, your doctor will use a stethoscope to listen to your heart and lungs, and will perform a physical exam. Other tests your doctor may order include blood tests, mucus cultures, breathing tests, and X-rays.

Treatment options for coughing up black mucus

Your treatment will depend on the causes of your cough. If you've been exposed to smoke, chemicals, or other hazardous substances, avoiding those triggers will be a primary focus. If there are signs of bleeding or infection, further evaluation may be necessary before deciding on a treatment plan.

At-home remedies

Typical at-home remedies include rest, hydration, and (if applicable) quitting smoking or avoiding smoke. Sometimes no treatment is necessary if you can avoid exposure to smoke or pollutants such as dust, grime, chemicals, or other agents. Other at-home remedies may include:

• Drinking hot liquids, such as herbal teas or soups
• Fresh lemon mixed with honey
• Over-the-counter cough medicines, including cough suppressants and expectorants
• Steam showers
• Salt water gargles
• Nasal saline spray or rinses

Antibiotics, antivirals, or antifungal agents

Depending on what your health assessment reveals, your doctor may prescribe antibiotics, antiviral medications, or antifungal agents. In some cases, doctors might also prescribe steroids to help reduce inflammation and speed up your recovery. Be sure to maintain open, ongoing communication with your healthcare provider, since some treatments can be challenging for patients to tolerate.

Oxygen and cancer therapy

It’s possible that coughing up black mucus is a sign of cancer. You may need to undergo oxygen therapy and cancer treatments, which could include surgery, radiation, chemotherapy, or other promising new targeted therapies.

When you should see a doctor about coughing up black mucus

If you were coughing up black mucus but it has already cleared up, you may not need to see a doctor. This is especially true if you’ve been avoiding smoking and pollutants. However, if the issue persists, watch for warning signs. Seek medical attention if you continue to cough up black mucus along with any of the following symptoms.

You should see a doctor if you have:

• Fever over 1010 F
• Nasal bleeding
• Sore throat
• Pus or black mucus in your throat
• Fatigue, malaise, weight loss
• Difficulty swallowing or breathing
• Making unusual sounds when breathing

You should go to the emergency room if you have:

• Chest or abdominal pain
• Difficulty swallowing or breathing
• Making unusual sounds when breathing or swallowing
• Persistent high or low body temperatures
• Hoarseness or loss of voice
• Bleeding from the nose or throat
• Confusion or disorientation

Questions to ask your doctor about coughing up black mucus

It is perfectly normal for you to have concerns if you’ve been coughing up black mucus or phlegm. Here are some questions to consider asking your doctor.

• When will I stop coughing up black mucus?
• Is my smoking the reason I’m coughing up black mucus? or being around chemicals at work?
• Am I contagious?
• Is the black mucus when I cough a sign of cancer or a serious medical condition?
• Could I have some type of infection?
• Do I need a chest X-ray or CT scan of my chest?
• Could this coughing up black mucus be related to my rheumatoid arthritis?

Frequently asked questions: coughing up black mucus

You may have additional questions for your doctor about coughing up black mucus. Following are some of the most frequently asked questions; they’re important, as they can help determine the most effective treatment for you.

Can vaping or using e-cigarettes cause you to cough up black mucus?

The full consequences of using e-cigarettes (vaping) are still unknown – but research has shown it to be harmful to your lungs. For example, vaping has been associated with lipoid pneumonia, a type of pneumonia that results from inhaling oily substances found in e-liquid. It is a rare form of lung disease for which there is no treatment other than stopping vaping – if it’s caught in time.

What if you’re coughing up black mucus after surgery?

Many patients cough up black mucus right after surgery due to irritation or minor bleeding in their throat or lungs. This mucus is usually temporary. However, if you continue to cough up black mucus after several days or weeks post-surgery, it could indicate a serious issue. Be sure to see your doctor, as this might be a sign of internal bleeding, infection, or a blood clot in the lungs known as a pulmonary embolism.

What if you’ve been coughing up black mucus for a week or longer?

If you’ve continued coughing up black mucus for more than a week, it could be a sign of an infection, a lung condition, or even a malignancy. Don’t ignore this symptom; seek medical advice as soon as possible.

Take care of your lungs

Coughing up black mucus can indicate exposure to smoke, toxins, or chemicals. It may also suggest an infection or signal a more serious medical condition, including cancer. With appropriate evaluation and treatment, you’ll hopefully get back to normal – only coughing occasionally with mucus that’s a normal, clear color.

General Medicine follows a strict editorial process, including using real experts to write our articles, vetted primary sources, fact-checking, a secondary medical review, and updates as necessary. This article was medically reviewed and fact checked by Dr. Pallabi Sanyal-Dey, MD.

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