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Chronic coughBy Mayo Clinic staff
Original Article: http://www.mayoclinic.com/health/chronic-cough/DS00957
Chronic cough — one lasting eight weeks or longer — is more than just an annoyance. A chronic cough can ruin your sleep and leave you feeling exhausted. Severe cases of chronic cough can result in vomiting, rib fractures and lightheadedness.
While it can sometimes be difficult to pinpoint the problem that's triggering your chronic cough, the most common causes are tobacco use, postnasal drip, asthma and acid reflux — the backflow of stomach acid, which can irritate your throat. Chronic cough typically disappears once the underlying problem is treated.
A chronic cough can occur with other signs and symptoms, which may include:
- A runny or stuffy nose
- A sensation of liquid running down the back of your throat
- Wheezing and shortness of breath
- Heartburn or a sour taste in your mouth
- In rare cases, coughing up blood
When to see a doctor
See your doctor if you have a cough that lingers, especially one that brings up sputum or blood, disturbs your sleep or affects your work.
An occasional cough is normal — it helps clear foreign substances and secretions from your lungs and prevents infection. But a cough that persists for long periods of time is usually the result of an underlying problem. Examples include:
- Postnasal drip. When your nose or sinuses produce extra mucus, it can drip down the back of your throat and trigger your cough reflex.
- 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. This type of asthma is frequently referred to as hyperactive airways disease.
- Gastroesophageal reflux disease (GERD). In this common condition, stomach acid flows back into the tube that connects your stomach and throat (esophagus). The constant irritation can lead to chronic coughing.
- Infections. A cough can linger long after most symptoms of a cold, influenza, pneumonia or other infection of the upper respiratory tract have gone away. An unusual, but not rare, cause of a chronic cough in adults is pertussis, also known as whooping cough in children.
- 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.
- Chronic bronchitis. This long-standing inflammation of your major airways (bronchial tubes) can cause congestion, breathlessness, wheezing and a cough that brings up discolored sputum. Most people with chronic bronchitis are current or former smokers.
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.
Having a persistent cough can be exhausting. The physical action of coughing depletes your energy reserves and disrupts your sleep. A chronic cough can also cause:
- Excessive sweating
- Urinary incontinence
- Fractured ribs, especially in women with fragile bones
Preparing for your appointment
While you may initially consult your family physician, he or she may refer you to a doctor who specializes in lung disorders (pulmonologist).
What you can do
You may want to write a list that includes:
- Detailed descriptions of your symptoms
- Information about medical problems you've had
- Information about the medical problems of your parents or siblings
- All the medications and dietary supplements you take
- Questions you want to ask the doctor
What to expect from your doctor
A thorough medical history and physical exam can provide important clues about a chronic cough. Your doctor may ask some of the following questions:
- When did your symptoms begin?
- Do you now or have you ever smoked tobacco?
- Does anyone in your family or workplace smoke?
- Do you cough up anything? If so, what does it look like?
- Do you take blood pressure medicine? If so, what type do you take?
- When does your cough occur? After meals? At night?
- Does anything relieve your cough?
- Do you get more short of breath with exertion? Or on exposure to cold air?
Tests and diagnosis
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Your medical history and physical examination help determine which tests your doctor will order. The goal of testing is to identify the underlying cause of your chronic cough.
- X-rays. Although a routine chest X-ray won't reveal the most common reasons for a cough — postnasal drip, acid reflux or asthma — it may be used to check for lung cancer and other lung diseases. An X-ray of your sinuses may reveal evidence of a sinus infection.
- Computerized tomography (CT scan). A CT scan takes X-rays from many different angles and then combines them to form cross-sectional images. This technique can provide more-detailed views of your lungs, but it's not a routine exam in the initial evaluation of a chronic cough. CT scans may also be used to check your sinus cavities for pockets of infection.
Lung function tests
These simple, noninvasive tests measure how much air your lungs can hold and how fast you can exhale. Sometimes you may also have an asthma challenge test, which checks how well you can breathe before and after inhaling a drug called methacholine (Provocholine).
If the mucus that you cough up is discolored, your doctor may want you to test a sample of it for bacteria.
These tests use a thin, flexible tube equipped with a light and camera to visualize structures within your body. To evaluate possible causes of chronic cough, this equipment may be inserted into your:
- Windpipe (trachea). This type of test, called a bronchoscopy, checks your bronchial tubes for signs of infection or obstruction.
- Nostrils. The video camera can help your doctor assess the status of the nasal mucosa and the openings to your sinuses.
- Esophagus. If your doctor suspects acid reflux is causing your chronic cough, he or she may want to examine the inside of your esophagus — the tube that connects your mouth to your stomach.
Treatments and drugs
Determining the cause of chronic cough is crucial to effective treatment. In some cases, more than one underlying condition may be causing your chronic cough.
Medications used to treat chronic cough may include:
- Antihistamines and decongestants. These drugs are standard treatment for allergies and postnasal drip.
- Inhaled asthma drugs. The most effective treatments for asthma-related cough are inhaled medications that reduce inflammation and widen your airways.
- Antibiotics. If a bacterial infection is causing your chronic cough, antibiotics will be prescribed.
- Acid blockers. When lifestyle changes don't take care of acid reflux, you may be treated with medications that block acid production.
- Cough suppressants. If the reason for your cough can't be determined, your doctor may prescribe a cough suppressant, especially if your cough is interfering with your sleep.
Lifestyle and home remedies
In many cases, there are measures you can take at home to help ease your chronic cough. Examples include:
- Avoid allergens. If your chronic cough can be traced back to nasal allergies, try to avoid the substances that cause your symptoms.
- Quit smoking. The most common cause of chronic bronchitis, smoking irritates your lungs and can worsen coughs caused by other factors.
- Reduce acid reflux. A cough caused by acid reflux can often be treated with lifestyle changes alone. This includes eating smaller, more frequent meals; and waiting three to four hours after a meal before lying down. If the cough is worse at night, elevating the head of the bed 4 to 6 inches (10 to 15 centimeters) can be very helpful.
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