Describe what happens in an allergic reaction?

Answer 1

depends really:

if it is an allergy to nuts then the mouth and lips can swell, the upper airway can close making it hard to breathe, you might break out in a rash or hives, you might throw up or have diarrhoea, you might have stomach pains or you might pass out. it wont be all of these at once or possibly at all. it might only be one or 2. the same goes for bee stings except i dont think your mouth and lips swell.

in a reaction to flowers you might start sneezing or coughing. it all depends on what the person is reacting to.