What are the main symptoms of anaphylaxis?

There are a few: Anaphylaxis is the term given to a systemic hypersensitivity reaction. It's where the body's immune system identifies a "harmful" substance and generates a reaction to it. The symptoms typically consist of a hive-like rash, redness, a rapid heart rate and sweating. This can progress to swelling of the throat and a drop in blood pressure that leads to fainting. Overall it is a dangerous reaction.

Several: Anaphylaxis commonly manifests in several areas- skin: hives or flushing. Low blood pressure: light-headed, dizzy, passing out. Bronchospasm: wheezing, shortness of breath. Patients also frequently describe a sense of impending doom- "i knew something was really wrong".