What is a Cough?
A cough is a spontaneous reflex action which protects your lungs and airways from irritants. This is because your throat and connecting airways contain nerves that are sensitive to mucous, dust and bugs. Coughing is the body’s way of helping to clear them.
A cough can be acute (short term), subacute, or chronic (long term), depending on the cause. (1)
Whilst coughing can be very annoying and inconvenient, it’s our body’s method of protecting and defending our airways. It is also part of the healing process for our respiratory system.
There are many reasons why we cough including irritants like smoke and mucous, allergens like pollen and dust or medical conditions. A cough is a symptom of these various things that affects the respiratory tract.
They can be broken down into the three categories we have already mentioned. As subacute is a continuation of an acute cause we will cover these together.
Acute and Subacute Cough
Upper Respiratory Tract Infections
URI’s are some of the most common respiratory infections. They include the common cold, influenza, laryngitis, epiglottitis and sinusitis, yet whooping cough and croup are two URI’s mainly affecting children.(2,3,4,5)
Apart from making us feel unwell, these types of infections cause fever, runny noses and a cough.
Coughing can spread these types of infection to other people, which is why it’s important if you have one to cover your mouth when you cough.
Furthermore, practicing good personal and general hygiene can help prevent the spread of these bugs. (6)
The medical term for hay fever is allergic rhinitis. This condition is an allergy to pollen and is prevalent in spring and summer when plants are growing and blooming.
It causes itchy eyes, sneezing and coughing (7)
Some fumes and vapours can cause irritation and inflammation of the airways. These could come from things such as cleaning materials like bleach or smoke. Dust and mold are also irritants that affect the airways.
It’s the Irritants which cause you to have a dry cough (8,9)
Asthma is a lung disease which causes inflammation and narrowing of the airways. It can affect people of all ages but usually starts when we are children. In fact it is believed there are up to 25 million asthma sufferers in the United States alone. (10)
This disease causes tightness in the chest and shortness of breath accompanied by coughing. Dependant on the severity of the asthma the cough can be acute or chronic. (11)
Chronic Obstructive Pulmonary Disease (COPD)
COPD is a disease affecting the lungs and the airway. It is prevalent among smokers and causes inflammation and obstruction of breathing channels.
Symptoms include breathlessness and cough. However, if the disease is chronic then the cough can also follow suit. (12)
Lower Respiratory Tract Infections (LRTI)
LRTI’s infect the airway below the throat. They include conditions like bronchitis and pneumonia and these infections can be both viral or bacterial. (13)
These kind of illnesses cause inflammation of the lower airway and lungs which produce a cough. (14)
A pulmonary embolism is a blood clot that travels to an artery in the lung and suddenly blocks it. The origination of the clot is usually in veins in the legs and it’s a potentially life-threatening condition if not diagnosed quickly. (15)
The symptoms include shortness of breath, chest pains and difficulty breathing. It’s also possible to develop a cough that may include coughing up blood (16)
You have two thin layers of tissue that line your chest cavity and wrap around your lungs, between these two layers there is a space called the pleural space. Irritation or inflammation can occur in this void which causes these two layers to rub against each other.
The most common cause of pleurisy is a viral infection, but there are others including cancer, bacterial infections and autoimmune disorders. However, the main symptom of this condition is sharp stabbing pain which is exacerbated by coughing or sneezing or breathing deeply.
Pleurisy can also cause shortness of breath, fever, chills and a cough. (17)
Heart failure happens when your heart is unable to pump sufficient amounts of blood to meet the body’s needs. Although this doesn’t mean your heart stops working, it’s just not working efficiently enough. (18)
One of the symptoms of heart failure is a cough and it tends to be worse when you are lying down, like at night when in bed. (19)
Gastroesophageal Reflux (GERD)
GERD also called acid reflux happens when food and acid from your stomach re-enters the esophagus. This could be because the muscle between the esophagus and the stomach doesn’t close properly. (20)
Typical symptoms of this condition are acid regurgitation, heartburn, bloating and nausea. Other symptoms include wheezing, hoarseness and a chronic cough. (21)
Chronic Lung Infections
These types of infection include conditions like cystic fibrosis, bronchiectasis and tuberculosis. They cause a cough which is chronic and persistent. (22)
The main cause of death from cancer in the US is lung cancer and the number one cause of this type of cancer is down to smoking. (23)
Among the many symptoms of this disease is a persistent cough that can get worse over a period of time. (24)
ACE inhibitors are medications prescribed for high blood pressure. This medication has side effects, the most common of which is a dry cough. (25)
We have already mentioned a cough is a symptom in itself. We have also looked at the different causes of acute, subacute and chronic cough. Yet this sign can be further categorised as follows:
This type of cough is one that can also be called a wet cough. It’s where the cough produces phlegm which can help clear the airways. (26)
A dry cough can feel like something is tickling the inside of your throat and does not produce any phlegm. (27)
As the name suggests, this cough happens at night, it may be productive or dry.
This is the term used to describe a cough that produces blood or sputum that contains blood. (28)
Diagnosis of a cough will include looking for any underlying causes. Your doctor will ask questions to ascertain the type of cough you have and how long it has lasted. If your cough is productive they will want to know if it contains blood.
Other factors for consideration are whether you have any allergies, if you smoke and if you have any medical conditions. Also, any recent travel or contact with people who have infections will be taken into account.
A physical examination will involve checking your pulse and temperature. A stethoscope will be used to listen to your heart, lungs and your ears, throat, legs and skin will also be looked at.
There are also further tests that may be required. These include blood and phlegm samples and maybe a throat swab. Other diagnostic tests are:
This gives a picture of your heart, lungs and blood vessels inside the chest and it can show up any underlying disease. (29)
This provides a more in depth picture of what is going on in your chest. (30)
This test measures how well your lungs are working and your breath as you inhale and exhale. (31)
This procedure uses a thin tube style instrument inserted through your nose or mouth. It has a light and a camera to examine the inside of your respiratory system.
This procedure will show a doctor if you have any tumors, bleeding or blockage in your lungs. Samples can also be taken at the same time. (32)
Methacholine Challenge Test
Methacholine is a drug which causes your airways to narrow. Doses are given in increasing numbers with a breathing test between each.
This is what’s commonly used to diagnose asthma. (33)
What is a cough? Cough is a spontaneous reflex action which protects your lungs and airways from irritants. Coughing is also the body’s way of helping clear mucous, dust and bugs from your airway.
What causes cough? Cough is a symptom of many conditions. Some are acute like cold and flu, irritants and hayfever. Others are considered chronic like GERD, cancer and chronic lung infections.
How do doctors test for cough? As cough is a symptom rather than a condition doctors will diagnose the type of cough to ascertain underlying causes. There are a number of tests that can be done to detect diseases and conditions that cause cough.
When should you go to the doctors with cough? Whilst a cough may go away on its own accord there are times when you should see a doctor. These include: a cough that has lasted more than 3 weeks or one that has escalated quickly. Also, seek medical advice if you have chest pain difficulty breathing or swollen glands. Further causes for concern are a cough accompanied by unexpected weight loss or a weakened immune system. (34)
Can you prevent cough? Some causes of cough like cold and influenza can be prevented by following some guidelines. Stay away from people you know are sick. You can also practice good hygiene by washing your hands regularly and avoid touching your eyes nose and mouth too often. (35)
What can relieve cough? A pharmacist can advise you and supply lozenges and syrups that may help relieve your cough. (36)
Will honey help my child’s cough improve? Many medications for cough cannot be used by children under 12. Honey has shown to be an alternative that can help relieve the symptoms. (37)
Should my doctor give me antibiotics for my cough? It would depend on the cause of the cough. Antibiotics can help with bacterial infection but will be ineffective against viruses. Antibiotics will also not help clear a cough associated with the common cold. However, your doctor will decide what is best for you. (38)
Cough is a spontaneous reflex action which our body uses to clear our lungs and airway. You will also find it can be short lived or persistent, productive or dry.
Cough is a symptom of many conditions and diseases, of which some are minor and go away relatively quickly like common colds, influenza or minor irritants. Others are more serious and have long term effects like cancer and GERD.
A cough can be bothersome and irritating but it is the body’s way of trying to protect our breathing system.
If you do find yourself with a cough, your doctor can use tests to help diagnose the cause and therefore provide the appropriate treatment.