Changes

Scientists think both genes and the environment have something to do with it. Normally, your immune system fights germs. It is your body's defense system. In most allergic reactions, however, it is responding to a false alarm.

Scientists think both genes and the environment have something to do with it. Normally, your immune system fights germs. It is your body's defense system. In most allergic reactions, however, it is responding to a false alarm.

Allergies can cause a runny nose, sneezing, itching, rashes, swelling or asthma. Symptoms vary. Although allergies can make one feel bad, they are usually not fatal. However, a severe reaction called anaphylaxis is life-threatening.

Allergies can cause a runny nose, sneezing, itching, rashes, swelling or asthma. Symptoms vary. Although allergies can make one feel bad, they are usually not fatal. However, a severe reaction called [[anaphylaxis]] is life-threatening.

[[Category:Medicine]]

[[Category:Medicine]]