An apparatus and method are disclosed for modifying a liquid enteral nutritional product during delivery thereof from a supply to a feeding tube delivering the modified liquid enteral nutritional product to the gastrointestinal tract of a patient. At least one beneficial agent not in controlled release dosage form in a useful, dose unit, amount, is disposed within a formulation chamber so as to be taken up in a liquid enteral nutritional product traversing the formulation chamber while feeding the modified nutritional product into the gastrointestinal tract of a patient. The beneficial additive(s) are selected from nutrients, medicaments, probiotics, or diagnostic agents, or mixtures thereof, each in a dosage form that is dispersible in the medium of the liquid enteral nutritional product in less than two hours.