What's the difference between allergies and asthma?

What's the difference between allergies and asthma?

William Berger (Allergist and Immunologist) gives expert video advice on: What is "asthma"?; Can people die from asthma?; What causes asthma? and more...

Allergy is an overreaction of the immune system to things that are normally harmless. There's nothing very harmful about a pollen, a grass, a tree, or a weed, or a dust, or animal dander, but in people who are predisposed to allergies, they overreact. Now that overreaction can occur in different organs in the body. If it occurs in the nose, we call it hay fever or allergic rhinitis. If it occurs in the eyes we call it allergic conjunctivitis, and if it occurs in the lungs, we call it allergic asthma.Now asthma is an inflammatory disease of the lungs, and there are many triggers that can cause someone with asthma to have increased symptoms: exercise, cold air, viral infections, and allergies. So you can have asthma without having allergies, and you certainly can be allergic but it not infect your lungs. But in the majority of cases people with asthma do have allergies as one of their major triggers of their symptoms. And that's why it's important in every asthma patient to determine whether they do have allergies, because if they do and you treat them, you'll help benefit their asthma condition.