Basic principles in allergology and hypersensitivity reactions

Many clinical presentations in dermatology are based on hypersensitivity reactions, which may be caused by toxic effects, intolerance reactions or immune adverse events. For a better understanding, the classification, the clinical presentations, and the essential management will be covered. Unfortunately, terms in allergology are not used uniformly, which can lead to confusion. This chapter is based on the definitions used to classify food hypersensitivity reactions. The classification covers various hypersensitivity reactions and briefly touches on their mechanism. This chapter also adds typical examples from clinical daily practice as well as basic principles in diagnosis and therapy.