Immunoglobulin E–mediated food allergy (IgE-FA) can be life-threatening in children, and rates are rising in the United States. We now know that early introduction of allergenic foods can reduce the risk of IgE-FA. Food protein-induced allergic proctocolitis (FPIAP) (also called cow’s milk protein allergy and/or intolerance or non–IgE-mediated milk allergy) is an early, common form of food allergy presenting with bloody or mucoid stools, often together with fussiness and feeding difficulty. Not thought to be associated with IgE-FA, FPIAP is treated with avoidance of the trigger antigen, most commonly milk, for the first year of life. Guidelines recommend an oral challenge after short dietary elimination to confirm the diagnosis, but this is rarely done in clinical practice. Given that FPIAP is associated with both eczema8 and diet restriction, we hypothesized that children with FPIAP would be at increased risk for IgE-FA.