If somebody near you starts reacting, the first thing to do is believe them. Straight away. Even if they look completely normal to you.
Then go and get a grown-up. Loudly. This is one of the very few moments in life when interrupting an adult is exactly the right move, and nobody will be cross with you about it afterwards.
Grown-ups will ring for an ambulance if it looks serious, and they'll say the word allergy on the phone, because that word makes the people at the other end move faster.
Lots of allergic people have a plan their doctor wrote down, and grown-ups follow that plan, not me. My job is telling you what to do in the first ten seconds: believe them, and go and get somebody.
Somebody should stay with the person the whole time. Nobody should be sent off to the toilet on their own to see whether they feel better.
Don't hang about to see what happens. Waiting is the thing that goes wrong most often. Being wrong and quick is far better than being right and slow.
I can't help in a real emergency — I'm a drawing of an axolotl and I haven't got thumbs. Grown-ups can, and so can the emergency number. Go and get them.
Questions this page raises
Ezzie will have a go at any of these.