Causes of Persistent Cough
It is quite natural to have a cough due to cold or flu. Our body eliminates the allergens, pollutants and toxins from our respiratory tract through the mucus. Coughing occurs when there is excess mucus in the respiratory tract.
Excess mucus is usually a symptom of our immune system trying to expel germs and toxins through the mucus membranes. Coughing is hence a natural mechanism of the body to remove toxins bound to the mucus. When the toxins are completely removed from the body, the mucus secretion gradually declines and the cough subsides.
However, persistent coughing is not necessarily a sign of ordinary cold. If your cough refuses to heal within a month, it might signify the presence of a more serious illness of the respiratory tract.
Bronchitis causes inflammation of the bronchial mucous membrane. Bronchitis can be either acute or chronic. Virus and to a small extent bacteria are responsible for acute bronchitis. Chronic bronchitis usually causes chronic coughs. Smoking and prolonged exposure to pollutants increases the risk of chronic bronchitis.
Sometimes persistent cough can be a symptom of asthma. Asthma causes inflammation and narrowing of the airways. Difficulty in breathing, tightness of chest and coughing are the symptoms of asthma. Coughing usually increases in the night or in the early morning.
If irritants enter your respiratory tract, it causes coughing. Allergens can also trigger asthma. Smoking is also responsible for allergic coughs.
Tuberculosis
Tuberculosis is a deadly infection that primarily affects the lungs. Persistent cough, fever, weight loss, night sweat and blood in the sputum are common symptoms of tuberculosis.
COPD
Chronic obstructive pulmonary disease or COPD is a condition that gradually causes loss in lung function. Loss in the elasticity of the air sacs and airways, damage in the walls of the air sacs, inflammation of the air sacs or excess production of mucus that clogs the airways causes COPD. Smoking and prolonged exposure to irritants increases the risk of developing COPD.
Post-nasal drip
Post-nasal drip is characterized by excess mucus production in the sinuses. Rhinitis, sinusitis and laryngopharyngeal acid reflux causes post-nasal drip.
Lung tumor
Presence of benign or malignant lung tumor can also cause persistent cough.
