Approved by the Cancer.Net Editorial Board, 01/2019

Coughing is your body’s way of clearing its airways of irritants and protecting your lungs from infection. Cancer and its treatment can cause this natural reflex to occur.

There are 2 main types of coughs:

  • Acute cough. A cough that starts suddenly and lasts less than 3 weeks. It is also called a short-term cough.

  • Persistent cough. A cough that lasts more than 8 weeks. It is also called a chronic cough.

A cough that brings up mucus or other secretions is called a productive, or wet, cough. One that does not is called a dry cough.

A severe or persistent cough can affect a person’s quality of life by disrupting sleep and causing issues such as vomiting, dizziness, headaches, loss of bladder control, and muscle strains. Severe coughing can also cause rib fractures, especially for people with cancer that has spread to the bone.

Relieving side effects like a cough is an important part of your cancer care and treatment. This is called palliative care or supportive care.

Causes of coughs

Many factors can cause a cough. Sometimes there may be more than 1 cause. They can include:

Cancer. Certain types of cancers are more likely to cause a persistent cough:

Cancer treatment. The following types of treatments can cause a cough that usually stops when treatment does:

  • Some types of chemotherapy, including bleomycin (available as a generic drug) and methotrexate (Rheumatrex, Trexall, Xatmep)

  • Radiation therapy to the chest

  • Hormonal therapies, such as fulvestrant (Faslodex) and letrozole (Femara)

Other medicines. Some medicines used to treat cancer-related symptoms or other conditions can cause a cough while they are being used:

  • Nonsteroidal anti-inflammatory drugs (NSAIDS), used to reduce inflammation and pain

  • Angiotensin-converting enzyme (ACE) inhibitors, used to treat heart disease

  • Midazolam (Versed), used to relax patients before medical procedures

Cancer-related side effects. Symptoms or side effects related to cancer or its treatment can also cause a persistent cough:

  • Infections, such as pneumonia and bronchitis, which people with cancer are more likely to develop due to a weakened immune system

  • Pleural effusion, which is a buildup of extra fluid in the space between the lungs and the chest wall. About half of people with cancer develop it.

  • Pulmonary embolism, which is a blood clot in the lungs that can be a side effect of chemotherapy

  • Super vena cava syndrome, which can happen when a tumor blocks the super vena cava, a major vein in the body

Other health conditions. Certain health issues that you may have in addition to cancer can cause a persistent cough:

  • Chronic lung diseases, such as bronchiectasis or interstitial lung disease

  • Asthma

  • Gastroesophageal reflux disease (GERD)

  • Postnasal drip

  • Chronic obstructive pulmonary disease (COPD), including emphysema and chronic bronchitis

  • Heart failure

Other common factors. Common causes of coughing also include cigarette smoking, breathing secondhand smoke, and allergens, such as pollen, mold, and dust.

Diagnosing a cough

An occasional cough is usually not something to worry about. But if you develop a persistent or severe cough after being diagnosed with cancer or during treatment, or an existing cough worsens, talk with your doctor.

It is especially important to tell your doctor if you:

  • Cough up blood. This can be a sign that a cancer has spread to the lungs. Radiation therapy to the chest can cause you to cough up secretions with blood for a few days. This is a normal side effect of radiation therapy, but you should still tell your doctor.

  • Cough up colored mucus. When mucus is yellow, green, or foul-smelling, it may mean that you have an infection that needs to be treated.

  • Experience other symptoms with your cough. Tell your doctor about any new or worsening symptoms of your cough, such as shortness of breath, chest pain, fever, heartburn, vomiting, roughness in voice, trouble swallowing, or a sore throat.

To help figure out the reason for your cough, your doctor may ask you some of the following questions:

  • When did your cough start?

  • How long have you had this cough?

  • How often do you cough and how severely?

  • When does the cough occur?

  • What makes your cough better or worse?

Your doctor may also recommend certain tests, such as:

  • Chest x-ray. Takes a picture of the inside of the chest.

  • Computed tomography (CT or CAT) scan. Takes pictures of the inside of the body using x-rays and then combines these images into a detailed 3-dimensional image.

  • Lung function tests. A variety of tests that check how well your lungs work.

  • Blood tests. They can show if your body has an infection.

  • Heart tests. May include an electrocardiogram or echocardiogram.

Treating and managing a cough

Cough-causing health issues not related to cancer or its treatment should be addressed. For example, GERD may be treated with antacids, and asthma may be treated with steroids.

Other medicines used to treat or manage a cough include:

  • Mucus-loosening expectorants, such as guaifenesin (multiple brand names)

  • Cough suppressants, such as benzonatate (Tessalon, Zonatuss), codeine (multiple brand names), and dextromethorphan (multiple brand names)

  • Decongestants

  • Antihistamines

  • Cancer treatments that target a tumor causing the cough, such as chemotherapy, radiation therapy, and surgery

Talk with your health care team about which medicine is best for you.

Other cough management tips

These tips and methods may also help you manage your cough:

  • Avoid smoking and secondhand smoke

  • Take a hot, steamy shower to loosen mucus

  • Stay hydrated, which makes mucus in the throat thinner

  • Mild exercise can help open up your airways, but try to avoid exercise that is very difficult

  • Avoid anything to which you are allergic

  • Avoid throat-irritating aerosol sprays, like hairspray, deodorant, and cleaning products

  • Suck on cough drops

  • Try relaxation techniques, such as deep breathing

Related Resources


When Cancer Is Not Your Only Health Concern

Benefits of Quitting Tobacco Use

Health Risks of Secondhand Smoke

More Information

American Lung Association: Cough