Allergic response

An allergic response may cause harmful symptoms such as itching or inflammation or tissue injury.

This histamine will act on different areas of the body (eyes, throat, nose, gastrointestinal tract, skin or lungs) to produce symptoms of an allergic reaction.

[clarification needed] Some common symptoms include itchiness, swelling, running nose, watery eyes, coughing, wheezing, trouble breathing, hives, rashes, mucus production, or a more severe reaction anaphylaxis.

Common triggers of a reaction include foods, likes nuts, eggs, milk, gluten, fruit and vegetables; insect bites from bees or wasps (often a severe response occurs); environmental factors such as pollen, dust, mold, plants like grass or trees, animal dander; medications or chemicals.

Some people experience an allergic response to cold or hot temperatures outside, jewelry or sunlight.

Often these treatments include an antihistamine oral pill, nasal spray, or eye drops.