We cough for many reasons: something “goes down the wrong pipe,” resulting in a brief hacking fest. Our winter throat tickles may signal an imminent cold or flu. We experience that nagging cough that takes weeks to fade after illness. But what about that cough that lingers so long that weeks fade into months?

Coughing is a vital mechanism in the body’s defense against disease. When we cough, we help the body expel mucus, microbes and foreign particles from the respiratory tract, protecting the lungs from infection and inflammation. Chronic, or long-term, cough can be caused by a number of things, from sinus problems to inhaling foreign objects into the lungs (usually seen in children), but the following are 8 common causes of chronic cough:

1.    Asthma or Allergies

For some people, inhaling pollen, dust, pet dander and other airborne particles can trigger a reaction called allergic rhinitis, which can lead to chronic coughing while in the presence of such irritants (like pets) or during certain times of year. Allergic rhinitis coughing usually accompanies other symptoms, like stuffy nose and sneezing. If you suspect that you’re suffering from allergies, you can keep track of what brings on coughing attacks. If your coughing intensifies during spring or when you spend time gardening, or if your cough eases up after leaving your mother’s house and her new kitten, you probably have allergies. If you’re having a hard time pinpointing your allergy, your doctor can run a series of tests to pinpoint the allergen.

Asthma, a chronic lung disease in which the lungs' airways are prone to swelling, causes coughing, typically along with chest tightness, wheezing and shortness of breath. Asthmatics usually have allergy triggers, along with negative responses to exercise, colds, cigarette smoke and airborne irritants.

2.    Chronic Obstructive Pulmonary Disease (COPD)

COPD, a lung condition that includes chronic bronchitis and emphysema, is a common cause of chronic cough. COPD develops when the airways and air sacs in the lungs become inflamed or damage, commonly a result of smoking. The lungs of COPD patients produce excess mucus, which the body tries to expel by coughing. If you suspect that you have COPD, especially if you are a smoker, your doctor may conduct tests to confirm a diagnosis, including spirometry, when a patient is asked to inhale as deeply as possible and then exhale into a tube.


3.    Gastroesophageal Reflux Disease (GERD)

GERD is a condition of the stomach and esophagus caused by stomach acid backing into the esophagus due to a weak valve. While GERD’s main symptom is severe heartburn, chronic cough, chest pain and wheezing are also common symptoms. While it’s not given the same attention as other causes on this list, GERD is a fairly common cause of chronic cough.

4.    Respiratory Tract Infection

Coughing is most associated with colds, influenza and other respiratory tract infections, typically accompanied by stuffy nose, fever, body aches and fatigue. Typically these symptoms last for days, unless the infection causes pneumonia, which can be caused by both bacteria and viruses. Persistent cough that produces green- or rust-colored phlegm is one of the main symptoms of the illness, along with fever, chills, chest pain, weakness and nausea.

If you have a cold, over-the-counter medicines should help make you comfortable until it clears up on its own, although your cough can outlast the other cold symptoms while the air passages in your lungs remain sensitive and inflamed. Pneumonia is treated with antibiotics and generally clears up within two to three weeks, although, again, the cough can linger much longer.

5.    Air Pollution

Living in or traveling to an area with air pollution can cause a persistent cough. Even short-term exposure to fumes and air pollution (e.g., diesel exhaust) can result in cough, phlegm and lung irritation and can exacerbate other symptoms of allergies or asthma. Air pollution doesn’t just occur outdoors: Mold spores found in and around your home can cause wheezing and coughing when inhaled.

In the aftermath of Hurricane Katrina, there were so many reports of persistent cough when residents returned that the term “Katrina cough” arose. This cough was believed to have stemmed from mold caused by homes flooding, combined with the construction dust that filled the city during the rebuilding process.

6.    Acute Bronchitis

Bronchitis typically rears its ugly head on the heels of a cold, where the patient suddenly develops a hacking, wet cough -- a result of passageways in the lungs becoming infected and inflamed. The wet cough is typically accompanied by fever, chills, aches, sore throat and other flu-like symptoms.


While it’s not uncommon for the cough to outlast the illness by weeks, if the cough doesn’t go away within a month or if you develop bronchitis regularly, it may be a sign that you have chronic bronchitis, which is considered a form of COPD. You should consult your doctor.

7.    ACE Inhibitors

ACE inhibitors are a class of medications used to treat high blood pressure and heart failure issues. Of the about 42 million people taking ACE inhibitors, 20 percent will develop a dry cough, which can last for weeks after discontinuing medication.

While the cough may be uncomfortable, you should never stop taking heart medication without consulting your doctor. ACE inhibitors are important medications for lowering blood pressure. Talk to your doctor if you’re taking an ACE inhibitor and have developed an uncomfortable, dry cough.

8.    Pertussis

Pertussus, or whooping cough, is a bacterial disease with symptoms that include high fever, runny nose and characteristically, a violent cough that can inhibit breathing. Attempting to inhale air between fits of coughing produces a distinctive, high-pitched whooping sound that gives the disease its name. Fever accompanies pertussis in its early stages, but the cough associated with this disease can last for weeks after the fever goes away.

Most of us received a vaccination against pertussis as children and are at low risk for developing this disease. However, inadequate vaccinations for pertussis are one of the reasons why this once-rare disease is making a comeback. The number of cases in the United States has risen at an alarming rate over the past decade, especially among adolescents and adults, who may need a booster shot for more protection.

If you're not sure why you’re up all night hacking or disturbing your coworkers with your attacks, then it's time to see the doctor. Get to the root of your persistent cough.