Which of the following scenarios is most likely to cause shock?

A severe allergic reaction, also known as anaphylaxis, is a medical emergency that can lead to shock, specifically called anaphylactic shock. During this response, the body releases a flood of chemicals that can cause the blood vessels to dilate rapidly, leading to a significant drop in blood pressure. This can result in insufficient blood flow to vital organs, causing them to become deprived of oxygen and nutrients. Other symptoms of anaphylaxis can include difficulty breathing, swelling of the throat, hives, and gastrointestinal distress. The rapid onset and severity of anaphylaxis are critical factors that can lead to shock if not treated immediately with appropriate interventions such as epinephrine.

In contrast, minor cuts and bruises typically do not result in shock, as they do not usually lead to significant blood loss or systemic reactions. Allergic rhinitis, or hay fever, primarily causes respiratory symptoms and discomfort but is not severe enough to induce shock. Chronic indigestion, while potentially uncomfortable and indicative of other underlying issues, does not pose an immediate threat of shock, as it doesn't typically involve acute, life-threatening physiological changes.