Welcome to Just Answer
I would be happy to assist you, I need some additional information.
Does your child have any drainage from the nose or going down the back of the throat?
Does your child make wheezing noises as well?
Does your child have any known allergies?
Does your son seem to be extra sleepy, or fatigued?
Is your child exposed to allergens such as cigarette smoke on a daily basis?
Any fever, or other symptoms?
I await your response.
It appears you are offline, so I am going to answer your question, as I do not know when I will next be available.
My first thought is that your son needs to be tested right away for asthma! In a young child, sometimes a constant cough may be the ONLY symptom of asthma in a child! A child who was born with a low birth weight, or who has been exposed to cigarette smoke daily has a higher chance of developing asthma. Also a child with allergies may develop asthma more easy. Fatigue, chest tightness, cough, wheezing, rapid breathing, or fatigue may all be symptoms of asthma, but in a young child a cough may be the only symptom as well. You need to have your child evaluated by a pediatrician who will get the proper testing done to determine is indeed a possibility. Your child will likely need X-rays, and lung function tests. This may be a slow process but is much needed as this is ridiculous for your son to suffer as he is. Please call the pediatrician right away, or seek a second opinion if the normal doctor refuses to re-evaluate your son. I wish you the very best! Thank you!
Has he had X-rays?
Asthma is not very easily detected in a child of this age. For some, it starts with this cough, and keeps getting worse as the years progress. In fact the cough is more noticeable at night in a child with asthma. You may also notice him cough when he laughs excessively, or gets over exerted. Does this ever happen? Do you notice wheezing?
The coughing upon getting excited is also another symptom of asthma in a child. Please seek further testing. I normally would rule out an infection before suggesting asthma, however, if this has went on for over a year, this leads me to believe that asthma is most likely the underlying cause. Best regards.