Allergen immunotherapy is an effective modality for patients with allergic rhinitis, allergic asthma, and stinging and biting insect hypersensitivity. An effective dose of allergen is necessary to achieve the desired reduction of symptoms, but it is essential to balance the risk of anaphylaxis with the need to relieve symptoms. The allied health caregiver plays an important role in the “hands on” administration of immunotherapy and in the prevention and recognition of symptoms of adverse reactions as well as the knowledge of how to initiate expedient treatment of adverse reactions.