This article has been reviewed by Andrew Moore, MD, FAAAAI
Symptoms & Diagnosis
Cough is a very common symptom, with multiple causes, that most people have experienced at some time in their life. Common causes of coughing include viral upper respiratory infections, lung disease, heart failure, reflux, choking on food or other foreign bodies in your throat, side effects of certain medications, exposure to airway irritants, such as tobacco smoke, pollutants or perfumes, and habit. Most coughing is self-limiting, rarely lasting more than 1 to 2 weeks.
Chronic cough syndrome refers to a cough that persists for a longer period of time, usually defined as 6 weeks or longer. Often more than one cause can be present in individuals with chronic coughing.
Chronic cough syndrome can be associated with other symptoms, depending on the cause(s) of the cough. These include heartburn, or indigestion, wheezing (“whistling sounds” when you breathe), or shortness of breath (including a difficulty in getting a deep breath in or out). Some patients describe “chest congestion.” In addition, cough can be associated with a “drip,” or drainage down the back of your throat, as well as nasal congestion (“stuffy nose”), nasal drainage (“runny nose”) and sneezing.
Consulting with your allergist / immunologist is an important first step in figuring out the cause or causes of your chronic cough. Your allergist will take a carefully detailed history to determine if any associated symptoms are occurring with your cough. It is important to discuss and bring all medications you are taking to your allergist / immunologist, including prescription, over-the-counter, vitamins, supplements, herbal therapies and homeopathic therapies. The physical examination can also be helpful. These initial steps will help determine which tests, if any are needed, to find the cause(s) of the cough.
Investigations and Management
There are many methods used to diagnose the cause of chronic cough syndrome. Allergy testing can determine if you are allergic to any inhalant allergens (such as tree, grass or weed pollens, mold, pets or dust mites), as allergic rhinitis and associated post-nasal drip is an important cause of chronic cough. Allergy tests should be ordered, performed and interpreted by an allergist. It may be important to limit allergic and irritant triggers that can be found in the home and work environment. Masks can protect the airways from hazardous chemicals and irritants.
Many lung conditions can cause a chronic cough. Asthma is a common condition which can present with shortness of breath, cough and/or wheezing that is diagnosed by your allergy/immunology physician. Lung tests, or breathing tests, can help your allergist / immunologist diagnose the cause of the cough. Radiological tests include a CT (“CAT”) scan of your sinuses and a chest x-ray. Other tests may include a laryngoscopy, which is a procedure that can be performed in the office using a tube, or “scope,” to look inside your nasal cavities and throat.
Gastroesophageal reflux disease (GERD) can present with heartburn, or indigestion symptoms, and is also known as “reflux.” This can contribute to and be the cause of chronic cough syndrome. It is important to note that you may not even feel or sense the heartburn, you may simply have the cough. While there are certain procedures available to diagnose GERD, often your allergist / immunologist may place you on a GERD medication for a certain period of time and assess if your cough symptoms improve.
Certain high blood pressure (hypertension) medications such as ACE inhibitors (for example, lisinopril) can cause chronic cough syndrome, and your allergist / immunologist, working with your hypertension physician, may change your high blood pressure medication to see if your cough improves.
Finally, if diagnostic testing and management of these common conditions are not helpful, many patients can benefit from therapies to help decrease throat sensitivity, known as cough hypersensitivity syndrome (e.g. habit cough), that can contribute to cough. In these cases, your allergist may refer you to speech therapy and/or discuss the use of suppressing treatment with specific medications which can help decrease coughing fits.
A variety of treatment options exist for chronic cough syndrome, depending on the cause(s) or suspected cause(s). These include oral medications (liquids and tablets), nasal sprays and inhalers. Of note, many common over-the-counter medications are limited in that they often do not address the exact cause(s) of the cough. Medications such as codeine are not recommended for the treatment of chronic cough given concerns for addiction. In children, codeine is specifically not recommended for acute or chronic cough due to safety concerns.
Some people suffer from more than one condition that may be contributing to persistent cough. Therefore, management often relies in a multidisciplinary approach with the help of allergists, pulmonologists, speech therapists, otorhinolaryngologists and gastroenterologists working together to address your symptoms.
Learn more about asthma.