An allergic reaction is your body’s response to a substance that it deems dangerous or potentially deadly. Spring allergies, for example, are caused by pollens or grasses. A deadlier type of allergic ...

Anaphylactic shock is a rare but severe allergic reaction that can be deadly if you don't treat it right away. It's most often caused by an allergy to food, insect bites, or certain medications. A ...

If you or someone you’re with is experiencing anaphylaxis, call 911 or your local emergency services immediately. Help them use an epinephrine auto-injector (sometimes called an EpiPen) if they have ...

An allergic reaction, or rash, to amoxicillin can involve papules or hives. It usually clears after stopping amoxicillin. Anyone with an amoxicillin rash needs prompt medical advice, as some reactions ...

Learn adult first aid for someone suffering a severe allergic reaction, including signs and symptoms and what to do in an emergency. Anaphylaxis (also called anaphylactic shock) is a severe allergic ...

Infusion reactions, also known as acute infusion reactions or infusion-related reactions, are common adverse effects that can occur when a person receives medication intravenously. Infusion reactions ...

Reaction formation is a defense mechanism in which people express the opposite of their true feelings, sometimes to an exaggerated extent. For instance, a man who feels insecure about his masculinity ...