Cough is expulsion of air from the lungs with a sharp sound. Cough is essentially a protective mechanism to expel out foreign particles from the airways. There are numerous causes of cough. Cough is one of the most common causes of outpatient visits to the hospital. Depending on the duration it can be classified into – acute (<3week), sub-acute(3-8week) and chronic (>8week) cough.
Coughing is normal once in a while, but many times it’s a sign of serious disease.
Acute cough – most common cause is respiratory tract infection, pneumonia, pulmonary embolism and acute exacerbation of underlying lung disease.
Sub-acute or chronic cough can be due to upper airway syndrome, gastroesophageal reflux disease, lung infections such as tuberculosis, asthma, chronic obstructive pulmonary disease, interstitial lung disease, bronchiectasis, lung cancer, drugs such as ACE inhibitors, smoking tobacco and foreign body inhalation.
Types of cough
Sometimes patients cough without producing mucus or phlegm called as Dry cough. When patients produce mucus or phlegm it is called as Wet or Productive cough.
Complications of cough
Exhaustion, headache, insomnia, musculo-skeletal pain, dizziness, urinary incontinence, syncope, and cough induced rib fractures are the common complications.
Immediately consult your doctor if you have any of the following signs –
- Cough since more than or equal to a month
- Cough accompanied by blood or yellow mucus or phlegm
- Cough accompanied by severe chest pain
- Cough with loss of appetite and weight
- Cough accompanied by difficulty in breathing or noisy breathing
- Cough with bluish discoloration of nails and/or tongue
What tests would be needed?
Many a times giving medicines would be sufficient. However, in case of inconclusive examination and history further investigations may be required to clinch the diagnosis which include –
- Chest X ray – can see the condition of lung. It can help detect infiltrates in the lung such as pneumonia, tuberculosis and lung cancer. However, it should be avoided in pregnant females unless and until required urgently.
- Spirometry – breathing into a tube, may help detect diseases such as asthma and chronic obstructive pulmonary disease.
- Sputum examination – to check for bacteria, tuberculosis and fungus. Morning sputum should be given for sampling
- CT scan of chest and paranasal sinuses – in case if above basic investigations are inconclusive, a CT scan may be needed to better define the problem in the lung or paranasal sinues.
- Laboratory tests such a complete blood count, eosinophil count, ESR, blood sugar random, renal function tests and liver function tests may be required.
What precautions to take?
- Stop smoking
- Avoid trigger factors for allergy such as dust, pollens etc.
- Over the counter cough suppressants may be tried
What is the treatment of Cough?
- Treatment of underlying cause is the mainstay.
- Upper respiratory tract infection: in case of bacterial antibiotics are given, in case of viral infection symptomatics are given such as anti-histaminics, dextromethorphan and steam inhalation
- Asthma: inhaled steroids and bronchodilators and anti-histaminics
- COPD: Inhaled bronchodilators
- Upper airway syndrome: anti-histaminics and intra nasal steroids
- Gastroesophageal reflux: proton pump inhibitors, prokinetics, life-style modifications (exercise, weight reduction, setting fixed time for meal, gap of 2 hours between lying down and eating food, elevation of head end of bed)
- Drugs such as ACE inhibitors for hypertension may cause cough and should be changed in case of cough.