Overview, Causes, & Risk Factors
A cough is a sudden, noisy expulsion of air from the lungs.
What is going on in the body?
Coughing is usually a reflex response of the body caused by an irritation in the throat or windpipe. A reflex response means that the body does something automatically, without a person thinking about it. This reflex helps to protect the lungs from bacteria, viruses, dust, and other damaging substances. However, people can cough on purpose if they want or need to. There are many possible causes of a cough, ranging from allergies to lung infections and cancer.
What are the causes and risks of the symptom?
There are a number of things that can cause a cough, including the following:
ACE inhibitors, which are medications that are often used to treat high blood pressure
chronic obstructive pulmonary disease, also called COPD, such as emphysema
congestive heart failure, which can cause fluid buildup in the lungs and make a person cough
exposure to certain chemicals or gases, such as car exhaust
a foreign body in the windpipe, which can happen when a small child puts objects in his or her mouth
gastroesophageal reflux, or heartburn
lung or throat infections, such as strep throat, acute bronchitis, or pneumonia
miscellaneous conditions, such as a neurological disorder known as Tourette syndrome
postnasal drip syndrome, which occurs when mucus from the nose and sinuses drains down the back of the throat
tumors or cancer, including lung cancer
Other causes are also possible. Sometimes no cause can be found for a person's coughing.
Symptoms & Signs
What other signs and symptoms are associated with this symptom?
When a person has a cough, there are many things a healthcare provider may want to know, such as:
if anyone else the person knows has been coughing or sick
if the cough is constant or only occasional
if the cough is dry or brings up any mucus or phlegm and the color of the phlegm
when the cough started and how long it has been going on
whether any blood has been coughed up
whether the cough seems to be related to a certain time of year, which often happens when people have seasonal allergies
Other symptoms may also be asked about, such as whether the person has a fever, heartburn, runny nose, or weight loss.
Diagnosis & Tests
How is the symptom diagnosed?
The role of the healthcare provider is to help a person figure out why he or she is coughing. The healthcare provider will start with a medical history and physical exam. This may be all that is needed to diagnose the cause.
The healthcare provider may order blood tests or a chest X-ray. Lung function tests can help to diagnose asthma or emphysema
Prevention & Expectations
What can be done to prevent the symptom?
Preventing a cough depends on what is causing it. Avoiding smoking, for example, can prevent smoker's cough. Early treatment of gastroesophageal reflux and congestive heart failure can prevent coughing from these conditions or from the medication prescribed for them. Many cases of coughing cannot be prevented, but they can be treated.
What are the long-term effects of the symptom?
A cough that is severe can be annoying and prevent sleep and other activities. Most long-term effects are related to the underlying cause. For example, those who have lung cancer as the cause of their cough may die. Those who have acute bronchitis usually get better within a few weeks and have no long-term effects at all.
What are the risks to others?
If the cause of a cough is a bacterial or viral infection, the person can spread these germs to others.
Treatment & Monitoring
What are the treatments for the symptom?
The underlying cause of the cough should be treated if possible. Medications such as dextromethorphan or codeine can be used to suppress a cough. Persons with a tumor or cancer may need surgery, radiation therapy, or chemotherapy. Those who have a lung infection may need antibiotics.
Persons with asthma or emphysema may need medications to reduce the inflammation in the lungs and to help open the airways. Individuals taking ACE inhibitors for high blood pressure may need a different type of medication.
What are the side effects of the treatments?
Medications used to treat coughing may cause drowsiness, stomach upset, or allergic reactions. Surgery may cause bleeding, infection, or allergic reaction to anesthesia.
What happens after treatment for the symptom?
A person with asthma or emphysema may need treatment for life. Persons with infections such as acute bronchitis may need no further treatment or monitoring after they recover.
How is the symptom monitored?
An individual can monitor his or her cough and how it is responding to treatment. Any new or worsening symptoms should be reported to the healthcare provider.