<s>[INST] Hello Doctor,my son is 2 and 1/2 yrs old. This Jan we went to india when we came back to germany he joined a play group..since then he is having cough at times it s less at times it is cronic he was treated with antibiotics twice..anti mucous3-4 times for bronchitis once but it never goes away completely..it always revives dry cough with running nose a at times and his nose gets block when he sleeps....what is the cause please help we are really worried is it some kind of allergy...initially we thought it s because he is coming in contact with other children that may be a cause but there is no break. [/INST] Is their any family history of allergies in the family ? Has your son ever shown symptoms of allergic cough in the past? Since he is now in a play group and in contact with other child Chat Doctor.  A blood work up with an X-ray chest will be helpful to rule out bacterial infections. If there is no evidence of an infective pathology, an anti-allergic orally with nasal cortisone spray at bedtime should relieve the symptoms. </s>