Allergic Reaction Topic Guide

Allergic Reaction Allergic Reaction: An allergic reaction is an overreaction to a harmless substance. Symptoms and signs of an allergic reaction include hives, rashes, swelling, itching, wheezing, nausea, and even anaphylactic shock in severe reactions. Treatment involves avoiding triggers, taking oral antihistamines, applying antiinflammatory steroid creams, and using an EpiPen.

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