Tell your pediatrician if any of your family members have ever had Asthma or allergies because both pass on to generation.
The general diagnosis of asthma is done through a medical exam and a test that measures airflow in and out of the lungs. Diagnosing asthma in kids is not easy as they are not able to complete the airflow test which requires blowing very hard into a tube and nor they can describe their illness properly.
Various skin or blood test is performed to know whether the child has any allergies or not. Assessing the report of the blood test and symptoms altogether, the pediatrician prescribe you some medicines.