Reactions don't all look the same, which is annoying of them. Some are bumpy and itchy on the outside. Some are all on the inside, in the tummy. Some are in the breathing bits, and those are the ones grown-ups worry about most.
Somebody reacting might come out in lumpy red patches, or go puffy round the eyes and lips, or be sick, or say their mouth feels funny, or start coughing in a way that doesn't stop.
The frightening sort is when breathing gets hard. It has a long name — anaphylaxis — and it's the reason allergic people carry things around with them and have a plan written down.
A small reaction one time doesn't promise a small reaction the next time. That's the bit that catches people out. It's why a grown-up will take it seriously even when it looks like nothing much.
If a friend says they feel wrong after eating, believe them straight away and go and find a grown-up. Don't hang about to see whether it gets more interesting. Interesting is not what we want here.
I can tell you what reactions can look like. I can't tell you what's happening to somebody in front of you, because I'm a drawing and I can't see them. A grown-up can, and the emergency number always works.
Questions this page raises
Ezzie will have a go at any of these.