Functional constipation (FC) is one of the most common disorders in childhood and has a neg-ative impact on the quality of life of children. Scientific evidence regarding a causal relation-ship between FC and cow’s milk allergy is controversial, as it is also reported by the latest European Society for Paediatric Gastroenterology, Hepatology and Nutrition-North American Society for Paediatric Gastroenterology, Hepatology and Nutrition (ESPGHAN–NASPGHAN) rec-ommendations. In the case of FC, routine allergometric tests are not recommended and the cows’ milk-free diet is only proposed in the case of laxative-resistant constipation and only following the advice of an expert. Instead, after a careful review of the literature and in view of the many clinical cases encountered in our clinical practice, we believe that it is useful to propose cows’ milk-free diet as first line for the treatment of FC at least in pre-school children and in children with a personal or family history of atopy or with a previous diagnosis of cow’s milk protein allergy.
