Asthma is diagnosed with a medical exam and a test that measures the air?ow entering and leaving the lungs. But diagnosing asthma in children is more difficult. Children under 5 or 6 can’t easily take the lung test because they have to blow very hard into a tube.

Also, infants and toddlers can’t talk about how they feel, so you need to watch for symptoms and describe them to your child’s doctor.

Tell the doctor if anyone in your family has asthma or allergies, such as hay fever, hives or eczema, a disease that can make the skin red, blotchy and itchy. If so, it’s more likely that your child has asthma.

To help learn your child’s risk for asthma, the doctor may perform an allergy test. This can be done at any age. Your doctor also may prescribe one or more asthma medicines. If your child gets better while taking the medicine, it can be a signal that your child’s symptoms are due to asthma.