Feeding Intolerance in Formula-Fed Infants

Inclusion Criteria: Inclusion Criteria for Stage 1: * Singleton full term birth with birth weight of \> 2500g. * Infant between 0 and 60 days of age. * Discontinuation of medications that might affect gastrointestinal (GI) tolerance. * Infant is exclusively formula-fed a full-lactose, intact cow milk protein-based infant formula (CMF) for less than 7 days prior to enrollment. Inclusion Criteria for Stage 2: * Infant was fed according to protocol in Stage 1 of the study. * Infant was identified as being fussy using the Intolerance Assessment Tool in Stage 1. Exclusion Criteria: Exclusion Criteria for Stage 1: * Chromosomal or major congenital anomalies. * Suspected or known metabolic or physical diseases affecting infant feeding and/or metabolism. * Hospitalization, other than for delivery, prior to enrollment. * Severe uncontrolled eczema, visible bloody stools or milk protein allergy prior to enrollment. * More than 1 substitution of an infant formula other than full-lactose, intact cow milk formula (CMF) since birth. * Use of a prokinetic drug within 7 days before enrollment. Exclusion Criteria for Stage 2: * Infant's intolerance symptom was caused by another reason, for example known infection/illness, food allergy, or response to vaccination(s). * Infant has immunization(s) within 3 days of enrollment in Stage 2.