Insect venom allergy is known and feared due to their often dramatic allergic reactions. It is not rare – in Austria, about 3% of the population react to insect venom with general symptoms such as rashes, dizziness, and shortness of breath. About 5% suffer from exaggerated local reactions, consisting of several centimetre-large swellings at the sting site, which can persist for several days. A small swelling and mild pain at the sting site, however, is a normal response to insect venom. However, some individuals develop an immune response to poisonous components. When it comes to the formation of IgE antibodies, this leads to the development of an insect venom allergy. In contrast to other forms of allergies, insect venom allergies are not associated with familial clustering and genetic predisposition, which means that anyone can develop an insect venom allergy if he/she is stung more often. Allergy testing and treatment (or prophylaxis) should be carried out, because the immune system is stimulated with each sting, meaning that the reaction to the following sting may be much stronger. Insect venom allergies are very dangerous, often ending in an allergic shock. Insect allergy sufferers should always carry emergency medications in case of a sting. For moderate to severe reactions, vaccination with the appropriate insect venom is recommended. This is usually very well tolerated and provides almost 100% protection.