Different food allergies can have different characteristics, see Individual food allergies [link], but things they have in common are the need to avoid the food when shopping, cooking, eating out.
You will need to get used to scanning ingredients labels! The new food labelling law should make it easier to spot the most common allergens eg milk, egg, peanut. Many supermarkets publish lists of “free from” products online or on request eg Morrisons - https://groceries.morrisons.com, or Tesco - http://realfood.tesco.com. Some publish recipes as well! Also see Food Labelling.
You will need to highlight your child’s allergies, they may wish to see a formal letter from your doctor or dietician confirming the diagnosis. For more help, see the School section. Remember that foods are sometimes used in art, crafts or other practical work eg rice, pasta, lentils.
Also called co-sensitivity: this is the idea that when you are allergic to one thing, you may be at risk of being (or becoming) allergic to something else. For example, babies who are allergic to cow’s milk have a higher risk of egg allergy. Other examples are peanut and tree nut, peanut and pulses, one pulse and other pulses. If you are not sure about a particular food, you should ask your doctor whether it is something to be worried about or not, and whether testing is appropriate or not.