Coughing Up Mucus: 9 Common Causes (& How to Treat)

Updated in January 2024

Coughing up mucus is a natural defense mechanism that helps the body to get rid of secretions produced by the respiratory system. Coughing mainly occurs when there is inflammation in the bronchi or bronchioles caused by an infection. 

Some illnesses that can cause mucus to be coughed up are bronchitis, bronchiolitis and tuberculosis. If your wet cough does not improve within 5 days, you should see your doctor for assessment and to start appropriate treatment if indicated. 

To treat coughs with mucus, you should inhale nebulizers with saline, drink at least 2 L (over half a gallon) of fluids per day, and drink teas with expectorant properties, like onion peel tea. 

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What causes a wet cough?

The most common causes of a coughing up mucus are:

1. Common cold

Respiratory infections like the common cold can lead to coughing up mucus, as well as symptoms like a blocked or runny nose, headache, sneezing and fever.

How to treat: A cough with phlegm caused by a cold can be relieved by irrigating the nose with saline solution several times a day. Check out other natural remedies for the cold that you can prepare at home.

However, if the cough lasts more than 10 days or if you experience symptoms like a headache or fever, you should see your doctor for assessment.

Also recommended: Cold vs Flu: Main Differences, How to Treat & Home Remedies

2. COVID-19

Coughing up mucus due to COVID-19 is usually associated with other symptoms such as fever, sore throat, diarrhea and changes in taste. In more serious cases, patients may also present with shortness of breath.

How to treat: if you suspect you may have COVID-19, you should see a health care professional for COVID-19 testing.  Treatment may involve medications like acetaminophen and specific antivirals. The coughing with mucus tends to resolve as the COVID-19 infection improves.

In more serious cases with shortness of breath, chest pain or drowsiness, hospitalization may be necessary for more intensive treatment and monitoring.

3. Allergic rhinitis

Allergic rhinitis can lead to coughing with mucus, as well as other symptoms such as a runny nose and watery eyes. These symptoms tend to be triggered after inhaling smoke or exposure to dust or pollen. 

How to treat: You should avoid contact with substances that trigger your allergic rhinitis, like pollen or dust. You can also keep your home ventilated and dust frequently with damp cloths to help prevent symptoms. 

However, moderate to intense symptoms should be assessed by a family doctor or allergy specialist. If confirmed, the doctor may consider prescribing medications for allergic rhinitis, such as antiallergics and nasal corticosteroids.

4. Bronchitis

Bronchitis is a respiratory condition that is characterized by the inflammation of the bronchi. These are structures that are responsible for the transport of oxygen to and from the lungs. Due to changes in function caused by infection, it is possible to experience a productive cough, wheezing, shortness of breath and excessive fatigue. 

How to treat: Symptoms of bronchitis will normally disappear on their own, without having to complete any type of treatment. However, to promote recovery and relieve symptoms, the doctor may recommend some medication, like analgesic, anti-inflammatories, mucolytics and expectorants.

5. Bronchiolitis

Bronchiolitis is a condition that is more common in babies under 2. It is associated with inflammation in the bronchioles, which are the smallest, most narrow airways in the lung. It results in difficulty with airflow, causing shortness of breath, fever, persistent cough with mucus and wheezing. 

How to treat it: It is important for the baby to be assessed by a doctor so that symptoms can be managed. Normally, it is advised that the baby rests and remains well hydrated. Nebulizers may also be beneficial. 

6. Pneumonia

Pneumonia can also cause coughing up mucus, which is usually yellowish. It is also common to experience other symptoms with this infection, such as fever, weight loss and fatigue.

Also recommended: Is Pneumonia Contagious? Why & 8 Ways to Prevent

How to treat: If you suspect you may have pneumonia, it is important to see a doctor for assessment and treatment. Treatment for pneumonia usually involves antibiotics. However, sometimes treatment may need to be carried out in a hospital for IV medications and close monitoring. 

Learn more about home remedies for pneumonia that you can prepare to complement your prescribed medical treatment.

7. Tuberculosis

Tuberculosis is an infection disease caused by bacteria that can reach the lungs, and compromise lung function. Common symptoms include coughing up mucus and blood, pain with breathing and shortness of breath. 

How to treat: It is important for the doctor to assess the lungs to confirm a diagnosis. Treatment typically involves the use of a prescription antibiotic. It is important that treatment is not interrupted, as stopping an antibiotic can lead to regrowth and reinfection by the original bacteria, which can lead to symptoms and worsening. 

8. Sinusitis

Sinusitis is an inflammation of the nasal cavities caused by a viral or bacterial infection. It leads to an accumulation of discharge within the sinuses, which can cause headache, facial pain, nasal congestion, fever and coughing up mucus. Learn more about the symptoms associated with a sinus infection.

How to treat: To relieve symptoms related to sinusitis, it is important to facilitate the excretion of any accumulated secretion. This can be done with saline nose rinses. Learn how to irrigate your nose with our step-by-step guide. If the sinus infection is caused by a bacterial infection, you may need to see your doctor for a prescription antibiotics. There are also some natural options you can try to complement indicated treatment. 

9. Chronic obstructive pulmonary disease (COPD)

COPD occurs due to a chronic inflammation of the bronchi and bronchioles. It causes difficulty breathing, rapid breathing, shortness of breath, constant coughing, and mucus that is white, yellow or green. 

How to treat: Treatment for COPD should be guided by the doctor. The goal of treatment is usually to relieve symptoms and prevent any worsening or complications. The doctor may recommend the use of bronchodilators, corticosteroids or mucolytics, as well as respiratory physiotherapy.  

When to see the doctor

You should see the doctor if your cough is accompanied by green, yellow, bloody or brown phlegm, as these colors are a sign of microorganisms in the lungs which require treatment with antibiotics. Learn more about what your phlegm color can mean. 

You should also be assessed if you experience fever, hoarseness or shortness of breath, or if you have been coughing for over 3 days. The doctor may order a chest x-ray and a sputum test to evaluate your phlegm. Once a diagnosis is confirmed, treatment can be recommended.

How to get rid of a productive cough

When you have a cough with clear phlegm, you are advised to perform a nebulizer to thin-out the phlegm and improve breathing. You should cough forcefully anytime you feel mucus in your throat. Drinking at least 2 L (half a gallon) of water throughout the day can also thin-out the phlegm, making it easier to eliminate.

In addition. you can take teas with expectorant properties, like mallow tea with guaco and onion cough syrup. If the cough is persistent, the doctor may recommend the use specific cough syrups, which should be taken as prescribed.

Home remedies to treat a cough with mucus

Some home remedies to cure productive coughs include: 

  • Inhale boiling water with 1 tablespoon of coarse salt and 1 drop of eucalyptus essential oil 
  • Drink tea with onion peel and a pinch of white pepper twice a day 
  • Drink a juice made with 1 orange, 1 lemon, 1 teaspoon of honey and 3 drops of propolis extract 
  • Eat food that is rich in vitamin C like oranges, tangerines, and sweet bell peppers to boost the immune system. You can also make an orange juice with watercress and drink this every day. 

When you cough up mucus, it s important not to take any syrups that are aimed at treating drying-up coughs, as eliminating the secretions is key to preventing complications like pneumonia.