Epinephrine should be administered at onset of anaphylaxis (life threatening allergic reactions). But when the time comes, parents or guardians may wonder if the situation actually warrants an injection. After all, it seems like a dramatic thing to do.
For example, maybe symptoms don’t seem especially severe, or maybe there are no symptoms at all, you just know that the person or child consumed a certain allergen, or was stung by a bee.
As a general rule, when in doubt, use the epipen.