R.L.
Hi L.,
My 15-yo dd has a severe peanut allergy. If she has an accidental exposure, she takes benadryl first and waits to see if the symptoms progress. If they don't abate but don't improve w/in 10 - 15 min, she takes a second dose of benadryl. If there's still no improvement after another 10 minutes, or her symptoms get worse, she uses the epipen. Fortunately, she's only had to use the pen once.
Her allergist actually isn't happy with this protocol. In his opinion, she should take both the benadryl and the epipen at the same time, because the danger for her of progressing to anaphylaxis is pretty high. His concern is that she won't realize that she really needs to use the pen until too late, when she might no longer be able to administer the shot or it won't be as effective. He would prefer that she take the benadryl and the epipen shot at the same time. The jitteriness of the epinephrine is somewhat counteracted by the benadryl, but the dose isn't high enough to cause other problems if it wasn't actually "needed."
With a toddler, I would be concerned about his being able to communicate symptoms to know if things are getting better or not. Can you or his caregivers adequately monitor is respiration? What about his blood pressure (which will crash if he progresses to anaphylaxis)? Are you and his caregivers trained well enough to recognize other signs of distress?
The most important "treatment" for allergies is strict avoidance. This is really difficult to maintain in a preschool or elementary school environment because it's hard to get small children to practice good hand hygiene and safe eating habits. Is he allergic to nut dust generated by another child eating nuts near by? Does he react, either locally or systemically, if he touches nut products? If so, he can have a reaction if other children have not washed their hands after eating nuts and they share a toy, sleeping mat, touch the same door knob, etc. You should definitely talk to the preschool about making it a nut-free zone (and his elementary school, later on), to make sure he's as protected as possible. You may need to speak to the other parents at the preschool about this directly, so that they understand that the risks to your child are far greater than their child's desire to eat nuts at preschool.
Eventually, you'll have to teach your son how to be safe in a world that he can't control, but for now, you just need to keep him safe.
Good Luck!