Allergies develop when our body's defence system (immune system) reacts excessively to substances that are actually harmless, such as grass pollen, animal dander or insect venom. This overreaction manifests itself in a whole range of different conditions. It can take the form of a harmless skin rash, but can also end in life-threatening circulatory failure. Hay fever is an example of an allergy in which people are allergic to grass or tree pollen, which manifests itself in classic symptoms such as a runny nose, sneezing attacks and red, itchy eyes. Around one in five people in Switzerland is affected by hay fever. ¹ Treatment involves avoiding the triggering substances and, depending on the patient's wishes and the severity of the allergy, anti-allergic medication or causative allergen-specific immunotherapy. Urticaria, also known as nettle fever or nettle rash, manifests itself as a very itchy, red rash and wheals. It can occur as a result of an allergic reaction, but can also have other triggers. However, urticaria usually occurs without allergic triggers and is therefore not an allergy in the narrower sense. However, it is treated with the same medication as hay fever as a first step in therapy.

¹ Ballmer-Weber B.K. & Helbling A. Allergische Rhinitis. Swiss Med Forum. 2017;17(8):179–86.