Cough is reflex to your immune system to clear your airways of mucus and irritants such is dust and smoke. Rarely this is reason to be serious disease. When you have an occasional cough this is very normal for health and there is nothing to worry about it. But if your cough is persistence, if you feel pain in your chest, you have blood in your mouth, you are wheezing, this medical case need treatment to make your health better and to feel save and free from disease. When you have dry-cough it means your thick mucus does not produce any phlegm. When you have a chesty cough your phlegm is produced to help clear your airways. If your cough is small you should not worry about it. Your cough will be gone within three weeks and you do not have to use any kind of medicine to help you.
Causes for cough
- Smoking (When people are smoking or they are using other tobacco, they often cough. They have irritation of the throat or their lungs is damaged); 
- Postnasal drip (This is a reason for productive cough or you feel all the time that you have to clear your throat. But many experts are against this, they do not think postnasal drip is cause for cough). 
- Viral illness (When people are having cold they often cough). 
- Stomach acid which come in esophagus (If you have this symptom this is very serious indicator that you have gastroesophageal reflux disease (GERD)). 
- Infections (If you have infection on your lungs or you have infection on your upper airway passages, this will cause you a cough. If you have productive cough, this will be reason for: pneumonia, bronchitis, sinusitis, tuberculosis). 
- Chronic lung disease (If you are coughing all the time this can be serious indicator for your chronic obstructive pulmonary disease (COPD), this means that your situation is getting worse than you were used on it). 
- Cold, flu, laryngitis, sinusitis, whooping-cough-these are upper respiratory infections which affects on the throat, windpipe and sinuses
- Pneumonia, bronchitis-these disease are caused from lower tract infection which affects your lungs or your lower airways
- An allergy-which is reason for this two diseases: allergic rhinitis or hay fever
- Inhaled dust or smoke 
- Asthma, chronic bronchitis, chronic obstructive pulmonary disease-which are caused by flare-up of long term condition
Persistent cough: persistent coughs can be caused by:
- An allergy
- Smoking– if you are smoker your chance to get COPD are bigger than if you are not smoker 
- Chronic bronchitis-this is long term respiratory tract infection 
- Asthma-If you are in doubt that you might have asthma, for you the best solutions is to visit your doctor and to check yourself. Asthma not only that causes a cough, but also it can be reason for wheezing, chest tightness, shortness of breath 
- Bronchiectasis-In this condition there is serious damaging of your airways. Your lungs become abnormally widened
- Postnasal drip-Your mucus is dripping down your throat, the back of the nose. This can cause the conditions of rhinitis and sinusitis. 
- Gastro-oesophageal reflux disease (GORD)-Your throat is becoming irritated by leaking stomach acid
- Prescribed medicine-Certain inhibitors used in medicine for treating cardiovascular disease and high blood pressure is found to cause persistent coughs in many people.
When to see your doctor? If you are coughing in the most cases you do not need to visit your doctor, because this situation is getting better for two or three weeks. But it is getting worse and you have persistent cough for more than three weeks. If your cough is worse and particularly severe you should visit your doctor to give you treatment. If you feel pain in your chest, your throat is with blood and you are not breathing normal, this is big reason to visit your doctor. Also if you have other symptoms like unexplained weight loss, you feel that your voice is changing, or lumps or swellings in your neck, along with cough, you should go to your doctor, to make you tests and to give you best treatment plan for your health.
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