Last Updated 02/04/2021

Author:Mauricio Danckers, MD, FCCP

About Cough

Key facts about Cough
  • Coughing is an important human reflex that helps protect your airway and lungs.
  • Occasional coughing is normal. Coughing helps clear your throat and airway from bugs, mucus, and dust. Persistent cough with other symptoms, such as shortness of breath, mucus production, or bloody phlegm, could be a sign of a more serious medical problem.
  • Persistent cough is a common symptom of a problem in your lungs, but it can also point to disease of the heart, stomach, or nervous system.

Coughing is a natural body response. When mucus, germs, and dust irritate your throat and airway, your body responds by coughing. Similar to other reflexes, such as sneezing or blinking, coughing helps protect your body.

Your throat and airways are equipped with nerves that sense irritants. When these nerves are stimulated, they send a signal to your brain. The brain then sends a signal back to the muscles of your chest wall and abdomen to rapidly and forcefully take a deep breath in and breathe out really fast, trying to remove the irritation. This response is immediate and effective. Coughing can propel air and particles out of your lungs and throat at speeds close to 50 miles per hour.

How cough affects your body

Occasional cough is a normal, healthy response. Our throats and lungs produce a small amount of mucus to keep the airways moist and to have a thin covering layer that helps protect against irritants we may breathe in.

Cough also helps us remove any toxins we accidentally breathe in. As we grow older, the muscles we use to cough tend to lose power, and our cough may not be as effective as it once was. Mucus starts to accumulate, and our cough is less effective at removing toxins and irritants from our throat and airways, putting us at higher risk of lung infections.

Occasional cough is normal, but a cough that persists is not. If you have a persistent cough, you should tell your health care provider. Cough associated with other symptoms, such as runny nose, acid reflux, shortness of breath, chest pain, increased mucus production, or colored or bloody mucus, is most likely a sign of an ongoing disease.

How serious is cough?

Cough affects 10% of the world’s population. Illnesses such as the common cold can cause it. It’s also important to know that very serious diseases, such as pneumonia, collapsed lung, blood clots in the lung, and fluid in your lung, can also cause cough.

People who have a history of smoking, chronic lung diseases such as COPDasthma, seasonal allergies, acid reflux disease (called gastroesophageal reflux disease), lung cancer, and chronic infections such as tuberculosis, have chronic cough.

How serious cough is depends on the disease that causes it.

What causes short-term cough?

Common causes of acute (short-term) cough include:

  • Infections, such as the common cold
  • Allergies, such as hay fever
  • Breathing irritants and exposure to fumes and vapors
  • Asthma

More serious conditions that can cause short-term cough include:

What causes long-term cough?

Some causes of long-term cough, also called chronic cough, include:

  • COPD
  • Asthma
  • Medications (Some medications can cause dry cough.)
  • Chronic lung infections
  • Lung cancer

Symptoms of cough

Cough is seen in many medical conditions. It’s important to take notes on the duration, type, and features of your cough as well as any other symptoms that come with your cough. This information will be helpful to your health care provider when he or she looks for the cause of your cough and determines the most appropriate treatment.

Cough is a symptom. It’s classified by its duration and specific features. Cough can be the only symptom of an illness, or it can happen with other symptoms in diseases of the lung, heart, stomach, and nervous system. Common symptoms of cough include:

  • Shortness of breath
  • Decrease in your ability to tolerate exercise
  • Wheezing or a whistling breathing
  • Runny nose
  • Sore throat
  • Heartburn
  • Weight loss
  • Fever and chills
  • Night sweats
  • Difficulty swallowing or cough when swallowing

What are the risk factors for cough?

Risk factors include:

  • Cigarette smoking. Being a current or former smoker is a major risk factor for chronic cough. The cough is caused by breathing cigarette toxins or second-hand smoking directly into your lungs.
  • Exposure to someone with respiratory infections. Respiratory infections can be very contagious.
  • Allergies. People with allergies have an increased risk of developing cough when exposed to a specific allergy trigger.
  • Environmental. Some work places could have irritants in the air that you can breathe in and develop cough. High-pollution areas or using coal for cooking or heating can also increase your risk of cough.
  • Chronic lung diseases. People with asthma, enlarged airways (called bronchiectasis), COPD, and previous lung infections that have left scars on the lungs are at increased risk of developing cough.
  • Female sex. Women have a more sensitive cough reflex than men, increasing their risk of developing chronic cough.

Diagnosing cough

Many diseases, even if they’re not severe, can cause cough. Cough suppressant medication may help control the cough, but it’s important to find the reason for your cough. Your health care provider will work with you to find the reason for your cough and determine the best treatment.

Warning signs that may indicate a short-term severe disease include:

  • Shortness of breath
  • Chest pain
  • Rash or facial swelling
  • Coughing up blood (called hemoptysis)
  • Rapid breathing
  • Fevers

Your provider will ask you about your medical history and perform a physical exam. You may need to have tests to help your provider find the cause of your cough and start treatment. Remember to keep a record of your cough, and bring the list of all the medications you’re taking, including over-the-counter medications and supplements, to your appointment.

Your provider may need to order some tests to help diagnose your cough. These tests may include:

When should you see your health care provider?

Visit your health care provider if you have a cough that lasts.

Call 911 immediately if you have sudden onset of cough associated with:

  • Severe difficulty breathing
  • Swollen face and hives
  • Severe chest pain
  • Coughing blood

Call your provider if you develop cough and have:

  • Recently been exposed to someone who has tuberculosis or whooping cough
  • Shortness of breath
  • Fever
  • Bloody phlegm or phlegm with pus
  • New wheezing or wheezing that doesn’t get better with inhaler use
  • Worsening leg swelling and shortness of breath, especially when you’re lying flat

Treating cough

Treatment for your cough will change depending on what’s causing it. Your health care provider will give you information about how to treat the cause of your cough. If you have questions about treatment options, ask your health care team.

Self-treatment and managing your cough

Consider these tips to help manage your cough while your provider is treating its cause:

  • If your cough is caused by a contagious disease, avoid spreading the disease to others.
  • Stopping smoking is a great way to help control your cough. Stay away from people who smoke to avoid second-hand smoke.
  • If a specific irritant in the air of your home of workplace causes you to cough, try to avoid them.
  • If your cough is caused by specific allergy triggers, try to avoid them. For example, if you suffer from hay fever, avoid being outside when pollen levels are high. Check the local weather report daily. You can also wear protective respiratory gear approved by your provider.
  • An air vaporizer or a steamy shower helps decrease nasal congestion and soothe your throat and airway when they are irritated because of your coughing.
  • Work with your provider. Treatment of cough is not only tailored to its cause but to your lifestyle.
  • Sucking on cough drops or hard candy increases saliva production and helps relieve dry cough and sore throat.
    Note: Never give cough drops or hard candy to children under age 3 because of the risk of choking.
  • Honey soothes an inflamed throat and may reduce the frequency of your cough.
    Note: Don’t give honey to children under age 1 because of the high risk of botulism, a serious infection.
Prevent the spread of infection

Remember that you blow out 3000 droplets of saliva every time you cough. So, the risk of infecting others is high when you cough. Help prevent the spread of disease when you’re ill by:

  • Avoiding visiting public places
  • Avoiding shaking hands
  • Washing your hands frequently with hot water and soap for 15 to 20 seconds. Alcohol-based rubs are a good alternative
  • Covering your mouth and nose with a tissue when coughing or sneezing, and then throwing the tissue away. If no tissue is available, cough into your sleeve or elbow, not your hand
  • Avoiding touching your eyes, nose, and mouth.
  • Disinfecting surfaces you touch at home or work when you’re sick.


You don’t need to deal with your persistent cough by yourself. Your health care team wants to help you and will give you the information you need. Many times, you may need a health care team made up of different specialists to help you deal with your persistent cough. Ask them questions. Join local support groups.

When your health care team has found the reason for your cough, learn more about the specific disease that is causing you to cough. Here are useful links to more information: