Chronic Cough

chroniccough

What is a chronic cough?

An occasional cough helps to protect your lungs by expelling unwanted material and this is normal. However, a chronic cough is one that persists for a number of weeks, and produces sputum or blood, disturbs your sleep, or affects school or work should prompt a referral to your GP or a lung specialist.

Causes of a chronic cough  

There are a number of causes of chronic cough. Some of these include:

  1. Postnasal drip. When your nose or sinuses produce extra mucus, it can drip down the back of your throat and trigger your cough reflex.
  2. Asthma. An asthma-related cough may come and go with the seasons, appear after an upper respiratory tract infection, or become worse when you're exposed to cold air or certain chemicals or fragrances. In one type of asthma (cough-variant asthma), a cough is the main symptom.
  3. Gastroesophageal reflux disease (GORD). This is a common condition where stomach acid flows back into the tube that connects your stomach and throat (oesophagus). The constant irritation can lead to chronic coughing. The coughing, in turn, worsens GORD — a vicious cycle.
  4. Infections. A lingering cough post a viral or bacterial infection can occur.
  5. Blood pressure drugs. Angiotensin-converting enzyme (ACE) inhibitors, which are commonly prescribed for high blood pressure and heart failure, are known to cause chronic cough in some people.
  6. Chronic bronchitis. This is an inflammation of your major airways (bronchial tubes) can cause a cough that brings up colored sputum. Most people with chronic bronchitis are current or former smokers and may have other smoking related lung problems
  7. Idiopathic chronic cough.  All alternative diagnoses have been explored and excluded.

Other less common causes include:

  • Aspiration (food in adults; foreign bodies in children)
  • Bronchiectasis (damaged airways)
  •  Bronchiolitis
  •  Cystic fibrosis
  • Laryngopharyngeal reflux (stomach acid flows up into the throat)
  • Lung cancer
  • Nonasthmatic eosinophilic bronchitis (airway inflammation not caused by asthma)
  • Sarcoidosis (collections of inflammatory cells in different parts of your body, most commonly the lungs

Risk factors for a chronic cough

Being a current or former smoker is one of the leading risk factors for chronic cough. Frequent exposure to secondhand smoke also can lead to coughing and lung damage.  Women tend to have more-sensitive cough reflexes, so they're more likely to develop a chronic cough than are men.

When to see a doctor

See your doctor if you have a cough that lingers for weeks, especially one that brings up sputum or blood, disturbs your sleep, or affects school or work.  We offer a chronic cough service where a systematic approach to investigate and manage you.

Investigations for chronic cough

Some investigations that may be conducted include:

X-rays:  A routine chest Xray may be useful in looking for some causes of chronic cough such as lung cancer, pneumonia and other lung diseases. However it will not be helpful in looking for post sinus drip, asthma or reflux. An X-ray of your sinuses may reveal evidence of a sinus infection.

Computerized tomography (CT) scans. CT scans also may be used to check your lungs for conditions that may produce cough or your sinus cavities for pockets of infection.

Lung function tests.  These simple, noninvasive tests are used to diagnose asthma and COPD. They measure how much air your lungs can hold and how fast you can exhale. 

Your doctor may request an asthma challenge test, which checks how well you can breathe before and after inhaling the drug methacholine/mannitol.

Sputum Tests.  If you are producing sputum, this can be sent off to the lab to be tested for bacteria, fungi or other cells.

Bronchoscopy.  A bronchoscopy is a flexible camera that is used to look and inspect inside the airways.  

 

After all these tests, sometimes there is no explanation for why a cough is ongoing, in which case a diagnosis of "Idiopathic chronic cough" may be given.  

Medications to treat chronic cough

Management of chronic cough is aimed at treating the underlying problem and will be individualized. Treatment options include:

  • Antihistamines, glucocorticoids and decongestants. These drugs are standard treatment for allergies and postnasal drip.
  • Inhaled asthma drugs. The most effective treatments for asthma-related cough are glucocorticoids and bronchodilators, which reduce inflammation and open up your airways.
  • Antibiotics. If a bacterial infection is causing your chronic cough, your doctor may prescribe antibiotics.
  • Acid blockers. When lifestyle changes don't take care of acid reflux, you may be treated with medications that block acid production. Some people need surgery to resolve the problem.
  • Cough suppressants. If the reason for your cough can't be determined and it's causing serious problems for you, such as keeping you from sleeping, your doctor may prescribe a cough suppressant. However, there's no evidence that over-the-counter cough medicines are effective.
  • Other newer agents: There are newer agents (e.g. gabapentin) that have been trialed in smaller studies and can be used if other treatments are not appropriate or have not worked so don’t worry, there are a number of options.

Our services that may be necessary during your review process include review by an Ear, Nose and Throat Specialist, a Speech Pathologist, or a Gastroenterologist.

Speech therapy for chronic cough

When all the common causes of chronic cough have been investigated, managed and optimally controlled, sometimes people will have ongoing issues with Idiopathic Chronic Cough.  Speech therapy can be really helpful to control you cough if this is the case.  Speech therapy can be helpful in two main ways to improve the distress of chronic cough

  1. Increase conscious control over the cough. This requires learning about why the cough is ongoing, being aware of conscious control over cough reflexes and then learning how to suppress the feeling.  

  2. Reduce the irritation that triggers coughing. Learning techniques to slow the build-up of irritation e.g. changing fluid intake, breathing techniques etc

(Material from Hunter Medical Research Institute, Vertigan, Gibson, Theodoros 2008)

Other important points to remember

  • There is no easy cure. 

  • Treatment is hard work and will require considerable commitment from you. 

  • Although the speech pathologist can explain how to stop the cough, no one else can stop the cough for you. 

  • The cough usually won’t go away overnight. In fact it can take two to three months before you feel more in control of your cough. 

  • Some people require more specific throat and breathing exercises to assist gain control over their cough. Your speech pathologist will monitor your progress and alter your program accordingly. 

What life-style changes are important in chronic cough?

1. Avoid exposure to smoke

Smoking is extremely irritating, drying and damaging to the larynx. Cough receptors are located in the larynx, so having an external source of irritation is a perpetuating factor in chronic cough.  

2. Breathe through your nose

Your nose has three important functions. Your nose warms, cleans and humidifies the air.  So if you breathe through your nose the air will be warm, clean and moist when it reaches your throat and lungs. However if you breathe through your mouth the air will be cold, dirty and dry. It is no surprise that cold, dry and dirty air causes irritation. Therefore breathing through your nose will reduce irritation. It can be difficult to breathe through your nose if you are in the habit of mouth breathing. The best strategies are to breathe through your nose whenever you think of it.

3. Minimise intake of dehydrating substances

  • Alcohol (e.g. wine, beer and spirits)
  • Caffeine (e.g. tea, coffee, cola) are very drying and can increase irritation that leads to coughing.

4. Lifestyle strategies for Gastroesophageal reflux

  • Eat smaller portion sizes
  • Have your smallest meal at dinner
  • Aim for bed >2hrs from last meal
  • Raise the head of your bed

5. Inhale steam

Research has shown that inhaling steam adds moisture to the surface of your vocal folds. This promotes healing and reduces the risk of injury.

  • Fill your kitchen sink with boiling water
  • Place a towel over your head
  • Breathe in steam
  • Do not add anything to the water. Most substances that you add to the
  • water will cause dryness and irritation.

6. Drink 1-2L water daily

If you are not well hydrated your vocal folds will have to work a lot harder whenever you talk. Drinking adequate water will also promote healing and reduce risk of injury. Many people with chronic cough are poorly hydrated.

  • Aim to drink at least 1 1⁄2 to 2 litres of water a day unless you have a medical reason to be more caution with water intake
  • You need more water during hot weather and exercise
  • Drink water frequently throughout the day e.g. take small sips
  • Drink water when your throat feels irritated
  • If you don’t like water try adding small amounts of lemon, lime or orange juice, mint leaves, experiment with different temperatures.

7. Suck on non-medicated lozenges

This helps your salivary glands to produce more saliva and moisten the larynx.  Avoid menthol containing lozenges as these are more drying in the long run than beneficial.