Final answer:
Mr. Ely has experienced an allergic reaction to a drug, which is an immune response that is not dose-related and can range from mild to severe symptoms.
Step-by-step explanation:
Mr. Ely has experienced an allergic reaction to a drug, which is an immune response to a type of antigen called an allergen. These reactions involve the immune system reacting to a substance that is typically harmless to most people, triggering symptoms that are not related to the dose of the substance. Allergic reactions can range from mild symptoms, such as sneezing and itchy eyes, to more severe symptoms like hives or anaphylactic shock, especially with repeated exposure to the allergen. In the case of drugs, an individual might become sensitized to a certain medication, leading to an adverse immune response upon subsequent administration, which can include a variety of symptoms.