Allergic diseases are very common and include allergic rhinitis (hay fever), atopic dermatitis (eczema), urticaria (hives), chronic sinusitis (infections), asthma, food allergies, drug allergies, insect allergies, and anaphylaxis (life-threatening allergic reactions). If people knew what they were allergic to, and took proper preventative measures, they would not have nearly the amount of suffering or medication use.