1. Children and infants who react to peanuts are likely to react not only to other nuts but also sunflower oil. Watch for this in baby cereals, it was our first reaction
2. Reactions are usually worse the second and third times. I know some people say if you let them come in contact with the allergen enough they will overcome the allergy, I personally don't recommend this unless you have a trained professional suggest it and oversee it, I've seen it work the opposite...
3. Testing a small amount on a wrist or the top of a foot is sometimes a safe(r) way to test. Again, I don't recommend this but ask a doctor, some recommend it and some do not.
4. Intolerance for an allergen can become a full allergy at any time. If you have an intolerance for a food it is recommended you avoid it when possible and avoid large amounts all the time.
5. Small children may react differently to allergens from day to day. This is why allergy tests are not considered reliable until age 5
6. Do NOT give children under 5: nuts (yup, peanut butter too) they may develope an allergy if they eat them; honey, as it may create an allergy to bees or cause an immediate reaction; strawberry (as far as I know it's a high allergen, but I just heard that today and def fed my baby the baby foods with strawberry, my dr had no problem with it); children under 3 should not have eggs. I'm sure there's more, these are just the ones I know of.
7. If everyone in your family has an allergy to a certain medication your child has an increase chance. As far as my research shows most allergies are not genetic (my girl has an allergy i dont, but we share a medicinal one) but it seems some are more likely if they are in the family.
That's it for now, feel free to share your experiences or knowledge, and when I research more I'll share!!