Cough is a reflex of the body which helps clear the breathing passages of foreign particles, microbes, irritants, etc. It helps to keep the throat and airways clear. But frequent coughing may indicate that you have a disease. Coughs can be productive (sputum/phlegm producing) or non-productive (dry). Acute cough has a sudden onset and is present for less than three weeks and chronic cough lasts longer than eight weeks. Cough which lasts between three and eight weeks is called sub-acute cough.
When you suffer cough in which there is an expulsion of phlegm (the thick, mucous-like secretion that is generated in the respiratory tract), it is called a productive or wet cough. This type of cough is generally associated with a feeling of tightness in the chest and throat, or a slight feeling of breathlessness. Some people also notice that the cough gets worse when they talk. The presence of phlegm indicates a high level of infection of the structures in the respiratory tract.
Dry cough
When there is little or no phlegm that accompanies a cough, it is termed non-productive or dry. Sometimes, people with a dry cough will feel the presence of a lump in the throat; others may feel a tickling sensation and cough to get rid of it, but find no relief. It is usually seen in the case of allergies, those exposed to smoke or other irritants, or those with mild sinusitis and viral infections of the upper respiratory tract.
Cough reflex
The lower part of the respiratory tract and the lungs are sterile; if dust or allergens get into this space, it can lead to an infection. The body has a defence mechanism to prevent these from making their way into the lower respiratory tract – the cough reflex. When the sensory nerves there are stimulated by an irritant, it triggers a coughing bout.[a1]
Antitussives
These are a class of drugs like pholcodine, dextromethorphan and antihistamines that act on the brain and suppress the cough reflex. They treat dry coughs caused by colds, flu, and lung infections. In general, avoid consuming alcohol if you are taking antitussives. More about them here.
Codeine
Is an antitussive drug, which alone or in combination with other medicines) is used for symptomatic relief from cough. Generally, the dose is 5 ml every 3 to 4 hours. Codeine can be habit-forming. Do not take a larger dose or take it for a longer period of time than prescribed by your doctor. More about it here.
Dextromethorphan
A non-narcotic derivative of codeine that helps soothe minor throat and bronchial irritation. The usual dose is 5 to 15 ml (10 to 30 mg) every 6 to 8 hours. This drug will not treat a cough that is caused by smoking, asthma or emphysema. More about it here.
Pholcodine
An opioid cough suppressant that helps relieve dry cough and also has a mild sedative effect. Drug reactions include shortness of breath, wheezing or difficulty breathing, swelling of the face or other parts of the body, rash, and itching or hives on the skin. More about it here.
Antihistamines
Cough medicines that reduce the body’s production of histamine (chemicals that cause symptoms of allergy). It can in some cases alleviate cough but possible side effects outweigh the benefits. Although antihistamines are prescribed for adults, chronic cough in children should not be treated with antihistamines. Do not use antihistamines for chesty coughs as they make it harder to remove mucus from your lungs. Rather use expectorants. More about them here.
Expectorants
It is a class of drugs that helps relieve chest congestion caused by mucus. The common active ingredients in expectorants are guaiphenesin, ammonium chloride, and ipecacuanha. These compounds are present in very small quantities in the cough medicine, so, they normally do not have any side effects or do not interact with other medicines. More about them here.
Bronchodilators
It is a class of medicines that are generally used in cases of coughs as symptoms of asthma, COPD, and bronchitis. These medicines dilate the airways making it easier for the airflow to the lungs. Bronchodilators can be short acting that provide quick relief from symptoms and long acting that help control and prevent symptoms. More about them here.
Postnasal drip
When our body produces excess of mucus in cases of cold, flu, allergies, etc, it not only manifests as a runny nose but also runs down the back of the throat from the nose. This is a postnasal drip. It can trigger a sore throat and chronic cough which gets worse at night.
Phlegm
It is a mucus-like secretion produced by the respiratory system in cases of infections or chronic irritations. It could be transparent, white, yellow, green, brown or even red at times. It has a protective action – it helps throw out bacteria and irritants from the respiratory tract. Read more about the process of cough.
Sputum
When phlegm is expectorated (thrown out of the body), it is called sputum. It is usually tested in the lab in cases of chronic cough to figure out the infective organism. Read more about the process of cough.
Bronchitis
It is a respiratory disease in which there is an inflammation of the mucous membranes of the bronchi (airway passages of lungs). The membrane swells and grows thicker, thus narrowing the tiny airways. This causes breathlessness and cough spells. Sputum may also be produced.
Bronchitis can be acute or chronic. Acute bronchitis usually follows a cold or viral infection and lasts a few days or weeks. There is cough, with or without the production of sputum. 90% of acute bronchitis is caused by viruses and the rest 10% by bacteria. If there is productive cough which lasts for three months or more in a year for at least two years it is chronic bronchitis. Recurrent inhalation of irritants from cigarette smoking, air pollutants, occupational exposure, etc. can injure the airways and cause chronic bronchitis. Read more about why you shouldn’t neglect cough.
Chronic Obstructive Pulmonary Disorder (COPD)
It consists of a variety of diseases that produces an inflammatory response in the lungs. The two most common diseases are chronic bronchitis or emphysema. Chronic bronchitis is clinically described as consistent cough with sputum or phlegm that lasts for over three months. Emphysema is a disease in which the lung tissue is damaged over time and results in shortness of breath or wheezing. The two forms of COPD aren’t mutually exclusive and can happen together. COPD can be caused by smoking, environmental factors or pre-disposed susceptibility to the disease. Read more about complications of untreated cough.
It refers to uncontrolled cellular growth in the lung tissues. These lumps and tumours interfere with the normal functioning of the lungs, stopping it from performing its primary duty of providing oxygenated blood to the rest of the body. It is the most common form of cancer in men and women and caused 1.38 million deaths in 2008. Along with smoking there are various things other causes of lung cancer. Heavy exposure to asbestos, radon, uranium, arsenic, genetic predisposition, heavy exposure to second hand smoke and lung scarring from any prior illness can all cause lung cancer. Read more about why you shouldn’t neglect cough.
Wheezing
Wheezing is a continuous, coarse, high-pitched whistling sound produced during breathing due to narrowed airway tubes. It is a sign of a breathing problem and is mostly heard when exhaling (breathing out). Wheezing is a common symptom of lung disease. Asthma attack is the most common cause of recurrent wheezing. It can also be present in bronchitis, pneumonia, breathing a foreign object into the lungs, smoking, etc.
Lung diseases
They are diseases or disorders which occur in the lungs and disrupt its functioning. The lung is the primary respiratory organ which transports oxygen from the atmosphere into our bloodstream and dispels carbon dioxide from our system. There are mainly three types of lung diseases – airway diseases (eg. asthma and chronic bronchitis), tissue diseases (eg. pulmonary fibrosis) and circulation diseases (eg. pulmonary hypertension). Smoking, air pollution, arsenic, asbestos, uranium and arsenic can cause various lung diseases. The most common lung diseases are asthma, bronchitis, COPD, emphysema, lung cancer and pneumonia.
Influenza
Influenza, commonly called flu, is an infectious disease caused by RNA viruses (influenza viruses). Runny nose, sore throat, cough, chills, fever, muscle pain and weakness, severe headache, etc. are some of the symptoms. It may cause nausea and vomiting. Influenza is more severe than the common cold. It is typically transmitted through coughs or sneezes, by direct contact with bird droppings or nasal secretions or through contact with contaminated surfaces.
An infection mainly affecting the lungs, it is called by bacteria from the mycobacterium family. In tuberculosis, the patient has a chronic cough (initially dry and later turns to wet as the disease advances) that does not clear up even after two to three weeks, or even following treatment with antibiotics for a bacterial infection. In some patients, the phlegm coughed up may also contain traces of blood. More about TB here.
In patients with asthma, the coughing is accompanied by a typical “wheezing” sound. When the airways have grown narrow, the air moving out when the patient exhales encounters a strong resistance to its movement and this is responsible for the “wheeze.” Doctors also recognize the presence of a type of asthma called cough-variant asthma. In this, the only symptom is a dry cough; the patient does not have any other typical symptoms of asthma such as wheezing or difficulty in breathing. Although anyone may develop such asthma, it is more common in young children and unless some form of treatment is provided, it may develop into “classic” asthma.
Paroxysmal cough
A cough that occurs as brief spells in which a person coughs severely, in spasms, without stops in between is called a paroxysmal cough. The most common cause of such cough is infection by Bordetella pertussis which results in the illness we know as whooping cough.
Whooping cough
In this disease, the child coughs non-stop and this depletes all the air from the lungs; when he or she forcibly inhales to make up for this loss, there is a “whoop” sound immediately following the cough. Some kids also develop a blue face due to lack of oxygen in the blood; others may suddenly stop breathing in between coughing fits. If children who have not received the DTP vaccine begin exhibiting such a cough, it is best to rush to a doctor for help who will also check for whooping cough.
Bronchiectasis
A condition in which there is damage to the airways and they widen, collecting a lot of mucus which triggers off the coughing spasms.
Barking Cough
This term is more of a description of how the cough sounds than a medical term. Kids with viral infections of the throat and upper respiratory tract develop a typical cough that sounds like the bark of a dog. Most often, this type of barking cough is mild during the day and gets progressively worse at night.