Anaphylaxis is a severe allergic reaction that happens very quickly and can be life-threatening. It occurs when the immune system overreacts to something, like food, medicine, or insect bites, and releases chemicals that cause symptoms such as difficulty breathing, a sudden drop in blood pressure, rash, and swelling. It's important to treat
anaphylaxis immediately with an injection of a medicine called epinephrine to prevent a dangerous outcome.
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