Anaphylaxis

Anaphylaxis is an overwhelming response by the body to an allergic stimulus. It is an acute, severe allergic reaction which affects the whole body. This can be caused by an intake of food, an insect bite or sting, or something a person has come into contact with.

Anaphylaxis is not the same thing as anaphylactic shock. Anaphylactic shock occurs when anaphylaxis causes blood vessels to dilate (vasodilation) resulting in low blood pressure. The patient may also experience severe tightening if the chest (bronchoconstriction) making it difficult or impossible to breathe.

The common signs of anaphylaxis include:

• Reduced blood circulation
• Generalised rash
• Feeling faint or collapsing
• A fall in blood pressure causing the body to go into shock (anaphylactic shock)

A person suffering from anaphylaxis is seriously ill. It is more than just a rash such as those seen in people having a mild allergic reaction.

It is important to recognise the signs of Anaphylaxis so that it can be treated.

What should you do if someone shows signs of anaphylaxis?

• Summon help
• Find out if the person is carrying any remedy measures to treat their anaphylaxis, such as injector pen with adrenaline or epinephrine, and administer it.

Dr Peter Saul MB ChB DRCOG DCH MRCGP Allergy Specialist

10001  September 2011