Overview

A life-threatening allergic reaction called anaphylaxis can cause shock, a sudden drop in blood pressure and trouble breathing. In people who have an allergy, anaphylaxis can happen minutes after exposure to a specific allergy-causing substance, called an allergen. Sometimes, there may be a delayed reaction, or anaphylaxis may happen without an obvious trigger.

Some common anaphylaxis triggers include:

• Medicines.
• Latex.
• Foods such as peanuts, tree nuts, fish and shellfish.
• Insect stings from bees, yellow jackets, wasps, hornets and fire ants.