An allergy is a malfunction (immune response) of our defence system when it interacts with the environment or with medication, i.e., with non-infectious foreign agents. The body mistakenly produces antibodies and can respond with symptoms of inflammation. Allergic responses are mounted, for example, against pollen (hay fever), house dust mites, certain foods, animal hair etc., and can become noticeable in form of symptoms such as sneezing, itchy eyes, or skin rash.