How Common is Allergic Proctocolitis?

While no one knows exactly how many babies have Allergic Proctocolitis (AP), we do know that 2 or 3 children out of every 100 will have some kind of allergic reaction to milk. In exclusively breastfed infants, this number falls to 1 in 100 (1%) or less. Around 1 in 100 children will be allergic to soy. Unlike other allergic reactions, AP is more common in exclusively breastfed infants than those being fed formula.