Allergies are caused by an abnormal hypersensitive response of the immune system to allergens, normally harmless substances in the environment. Many allergies are quite mild and cause symptoms like a runny nose, watery eyes, red eyes, sneezing, rashes, hives, diarrhea, and sleepiness. Some allergies on the other hand are quite severe and can lead to anaphylaxis and death.
* The information on this site is for informational purposes only and should not be used for diagnosing, treating, or preventing any health problem.
