What is a secondary allergic reaction?

This week is Allergy UK's Allergy Awareness Week.

Today I am writing a post on secondary allergic reactions, also know as second or late phase reactions. 

This has been a harder task than I though it would be. 

I was not given lots of information on secondary reactions when I took L to the hospital after she had her reaction to the Snickers bar, only that they can happen and be worse than the first time, so to be aware of them and take her straight back to A&E if I was worried. 

I have tried to find information on the internet to get some official information for this post, but I have struggled to find more than a sentence or two on most websites.

The World Allergy Organization says that second phase allergic reactions can occur 1-8 hours after the initial reaction.

The Health of Children Website says that a second phase reaction can occur 4-12 hours after the initial reaction.

So I guess we should all just be aware of secondary reactions, and keep an eye on the patient for 12 hours after the initial reaction to be on the safe side.

Thankfully I haven't experienced a secondary reaction, but it is important to be aware that if either yourself or your child starts to feel unwell again, within that 12 hour period, that it could be a second phase reaction.  You do not have to have come into contact with the allergen again, it is a continued reaction to the first contact.  The patient may need further medication and will need monitoring.

For a more detailed explanation of an allergic reaction, including second phase reactions see this page from City Allergy

If anyone has additional information regarding second phase reactions, and would like to share, or if you would like to share an experience of a second phase reaction, I would be grateful and love to include on here.

Keep safe,

Lupin Girl x