OBJECTIVES: A pharmacoeconomic analysis was undertaken to determine costs, consequences and cost-effectiveness of a specific brand of partially hydrolyzed 100% whey formula manufactured by Nestlé (PHF-W), in the prevention of atopic dermatitis (AD) in “at risk” children when compared to standard cow milk formula (CMF) in Spain. METHODS: Based on a 12-month time horizon (including 6 months of formula consumption), an economic model was developed synthesizing treatment pathways, resource utilization and costs associated with the treatment of AD in healthy “at risk” Spanish newborns who were not exclusively breastfed.  Model inputs were retrieved from the literature, official formularies and expert opinion, including outcomes from a meta-analysis.  The treatment pathways considered a dietary management approach, a medical treatment approach and a combination thereof.  The final outcome was the expected cost per avoided case of AD, yielding an incremental cost per avoided case (ICER) of AD for PHF-W vs. CMF.  Outcomes were presented from three perspectives: the Spanish Ministry of Health (MOH), the subject’s family and society (SOC). A secondary analysis compared PHF-W to extensively hydrolyzed formula (EHF) in prevention. RESULTS: The expected number of avoided AD cases by selecting PHF-W over CMF was 2,787 cases in a birth cohort of 38,661 at risk infants.  The base-case analyses generated expected ICERs of €1921, -€1102 (savings) and €785 from the MOH, family and SOC perspectives, respectively. Cost drivers were formula from the MOH perspectives and time loss from the family perspective, with formula and to a lesser extent time loss for the SOC perspective.  PHF-W yielded approximately €10.7 million savings against EHF in the secondary analysis.  One-way and probabilistic sensitivity analyses confirmed the robustness of the model. CONCLUSIONS: Under a range of assumptions, this analysis has established the cost-effectiveness of PHF-W in the prevention of AD among Spanish infants.