Symptoms, Causes, Treatments, Questions & Related Topics

What is a Cough?

We’ve all experienced it at one time or another – that annoying tickle in the back of your throat that you just can’t seem to get rid of. Sure, coughing is annoying, but it can actually be a good thing, since it gets rid of any mucus or foreign materials in your body. It’s important to remember that a cough is not an illness, it’s a symptom of something else that is going on in your body. By evaluating your other symptoms, a medical professional can figure out what the cough means. 

Top 10 Cough Causes

1. Asthma

Asthma is a condition in which your airways become narrow, swollen, sore and inflamed, causing difficulty breathing.[1] Allergens and environmental irritants such as cigarette smoke, air pollution and certain foods can make your airways more sensitive when you have asthma. Exposure to these triggers can induce coughing, along with wheezing, chest pain and other symptoms.

Asthma usually begins during childhood and may be caused by genetics, respiratory infections, allergies and environmental toxins. Other risk factors for asthma include having eczema, working with chemicals and irritants in the workplace, and regular exposure to secondhand smoke.[2]

2. Gastroesophageal Reflux Disease

At least 25% of chronic cough cases are associated with gastroesophageal reflux disease, or GERD.[3] GERD happens when stomach acid or bile flows back into your esophagus and irritates the lining. This can lead to heartburn, difficulty swallowing and a dry, chronic cough.

Coughing itself can also cause reflux, triggering a cough-reflux-cough cycle. Any amount of reflux in the esophagus can cause the tubes that carry air to your lungs to reflex and start a cough. Risk factors for GERD include pregnancy, obesity and hiatal hernia, which is the bulging of the top of the stomach up into the diaphragm.

3. Common Cold and Flu

Viral infections, like the common cold and flu, are caused by tiny germs, or viruses, that hijack and damage your normal cells and cause them to multiply.[4] Viral infections make you sick when your immune system is unable to fight and overcome these cellular changes. Infections that affect your respiratory tract can lead to symptoms of sneezing, inflammation and coughing.

The common cold and flu usually produce a dry cough. People who suffer from asthma may experience a prolonged cough even after their viral infections have cleared. The average duration of a cough caused by viral infections is 18 days.[5]

4. Pneumonia

Pneumonia is an infection of one or both sides of the lungs that causes the air sacs to fill with pus.[6] This infection is commonly caused by bacterial, fungal and viral infections, like the flu and HPV. The inflammation triggered by pneumonia can lead to fever, difficulty breathing and a wet cough that produces phlegm.

Pneumonia can affect people of all ages, though infants aged two and younger and seniors aged 65 and older are at greatest risk. Environmental toxins, like pollutants and chemicals, may increase your risk for pneumonia, along with lifestyle factors, such as smoking and alcohol abuse. Medical conditions linked to a higher risk for pneumonia include lung disease, asthma and diabetes.

5. Chronic Obstructive Pulmonary Disease

COPD is an umbrella term used to describe a group of lung diseases that block your airways and cause difficulty breathing. Chronic bronchitis, emphysema and refractory asthma are just some lung diseases that classify as COPD.[7] In addition to breathlessness, symptoms of COPD include wheezing, chest tightness and a cough that produces a lot of phlegm.

COPD is mainly caused by long-term exposure to substances that irritate, damage, and inflame your lungs, such as dust, air pollution, and cigarette smoke. Smoking is the most common cause of COPD and accounts for almost eight of every ten deaths related to this disease. A genetic condition known as alpha-1 antitrypsin, or AAT deficiency, is also a risk factor for COPD and affects nearly 100,000 Americans.[8]

6. Allergies

Allergies are a condition in which your immune system reacts abnormally to substances that generally don’t affect other people. Allergies can be caused by exposure to animals, certain foods, and drugs and medications. Those affected by allergies may experience symptoms of itching, sneezing and coughing.

Allergies can affect anyone at any stage of their life and often cannot be prevented.[9] However, those who suffer from allergies may prevent allergic reactions by identifying and avoiding triggers. For instance, those allergic to peanuts can avoid exposing themselves to peanut shells and foods that contain peanuts to lower their risk for coughing and other allergic reactions.

7. Bronchitis

Bronchitis is a condition where the bronchial tubes or lung airways become inflamed and irritated to cause wheezing, difficulty breathing, chest pain and coughing.[10] The coughing triggered by bronchitis tends to bring up lots of mucus, which is the slimy substance produced by your bronchial tubes. Bronchitis may be short term or ongoing and can spread just like the common cold, flu and other viral infections.

Bronchitis can be caused by bacteria, viruses and exposure to environmental irritants that affect your lungs, like dust, fumes and cigarette smoke. Acute bronchitis tends to affect infants, young children and seniors more than any other age group. Chronic bronchitis tends to be more common among women, smokers, and people over the age of 45.

8. Post-Nasal Drip Syndrome

Post-nasal drip syndrome, or PNDS, is the steady dripping of mucus that runs down the back of your nose to the throat to trigger coughing.[11] Normally, the mucus from your nose mixes with saliva to drip down the back of your throat and is easily swallowed. But PNDS happens when your body produces a thicker or higher amount of mucus than usual, which drips steadily down the back of your throat, causing irritation and coughing.

PNDS is often caused by certain changes in your body and in the environment that trigger extra mucus production, such as seasonal allergies. PNDS can also be caused by cold weather, dry air, smoke and toxic chemicals from cleaning products, perfumes and environmental pollution.[12]

9. Smoking

Smoking and secondhand smoke can irritate and inflame your lung tissue and airways to trigger coughing. Long-term smokers who suffer from years of lung irritation can develop a chronic cough with mucus, as well as emphysema, for which coughing is a symptom.[13] Smoking may also lead to medical conditions that produce a cough, such as chronic bronchitis, COPD, respiratory infections and lung cancer.

10. Sinusitis

Sinusitis is when your sinuses, or the cavities around the nasal passages, become inflamed. Your sinuses produce mucus that drains into the nose.[14] When the nose becomes swollen, sinuses can get blocked, producing symptoms of headache, stuffy nose, sore throat and coughing.

Sinusitis can be caused by fungal infections, airborne pollutants and allergies. Risk factors for sinusitis include nasal polyps, weakened immune system and previous respiratory tract infections, like the flu.[15]

Possible Health Conditions Related to Cough

  • Allergies
  • Asthma
  • Bronchiectasis
  • Chronic bronchitis
  • Common cold
  • COPD
  • Flu
  • GERD
  • Heart failure
  • Lung cancer
  • Pneumonia
  • Post-nasal drip syndrome
  • Respiratory infections
  • Sinusitis
  • Upper airway cough syndrome
  • Whooping cough

Questions Your Doctor May Ask About Your Cough

  • How long have you had a cough?[16]
  • Is it a wet or dry cough?
  • Are you coughing anything up, such as mucus, phlegm or blood?
  • When did the cough start?
  • How often do you cough?
  • Do you have a history of allergies, asthma or other medical conditions?
  • Do you experience heartburn or a sour taste in your mouth?
  • Have you recently had the flu or a cold?
  • Do you smoke or spend time around others who smoke?
  • Are you taking any cold medicine or other medications?
  • Are you regularly exposed to air pollution, dust or fumes?
  • Do you experience wheezing or chest discomfort with your cough?
  • What time of the day is your cough at its worst?

Cough May Also be Known As



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