Which term describes an immune-mediated adverse reaction after prior sensitization?

Which term describes an immune-mediated adverse reaction after prior sensitization?

• A. Hyporeactivity
• B. Hyperreactivity
• C. Hypersensitivity
• D. Idiosyncratic reaction

Answer: (C)

The idea being tested is that immune-mediated adverse reactions after prior sensitization are called hypersensitivity. When the immune system has previously encountered a drug and becomes sensitized, a subsequent exposure can trigger an immune response that causes symptoms or tissue damage, rather than a direct pharmacologic effect of the drug. These reactions can be mediated by different immune pathways—from IgE on mast cells causing immediate reactions like anaphylaxis to T cells or immune complexes causing delayed or more complex responses. This range is captured by the term hypersensitivity, which specifically describes immune-driven reactions that require prior sensitization. Other terms don’t fit this pattern. Hyporeactivity means a reduced response to stimuli, not an immune-mediated adverse reaction after sensitization. Hyperreactivity isn’t the standard descriptor used for this drug-related context. An idiosyncratic reaction is unpredictable and not necessarily tied to prior sensitization or an immune mechanism.

The idea being tested is that immune-mediated adverse reactions after prior sensitization are called hypersensitivity. When the immune system has previously encountered a drug and becomes sensitized, a subsequent exposure can trigger an immune response that causes symptoms or tissue damage, rather than a direct pharmacologic effect of the drug. These reactions can be mediated by different immune pathways—from IgE on mast cells causing immediate reactions like anaphylaxis to T cells or immune complexes causing delayed or more complex responses. This range is captured by the term hypersensitivity, which specifically describes immune-driven reactions that require prior sensitization.

Other terms don’t fit this pattern. Hyporeactivity means a reduced response to stimuli, not an immune-mediated adverse reaction after sensitization. Hyperreactivity isn’t the standard descriptor used for this drug-related context. An idiosyncratic reaction is unpredictable and not necessarily tied to prior sensitization or an immune mechanism.