We recommend adding the daily supplement of Ready, Set, Food to your child's bottle, or mixed into solid food, at the beginning of the day to monitor any potential reactions that may occur 2-4 hours after consumption. To easily identify an allergic reaction, do not start using Ready, Set, Food if your baby is not feeling well. For example. if your baby is still getting over a cold, or toothache, etc. We recommend waiting until your baby feels better to start our program.