The Effect of Probiotics in Infantile Colic

Inclusion Criteria: * Age 3-12 weeks at screening; * gestational age 37+0 to 42+0 weeks; * birth weight appropriate or large for gestational age; * parent/caregiver/legal guardian older than 18 years; * exclusive or predominant breastfeeding (\>50%); * willingness to maintain feeding pattern and complete diaries and questionnaires; * physician-confirmed Rome IV infantile colic, parental report of ≥3 hours of crying/fussing per day on ≥3 days in the prior week, and ≥3 hours in at least one 24-hour period documented in the run-in diary; * written informed consent; mother available for scheduled visits; infant otherwise clinically healthy. Exclusion Criteria: * Severe gastroesophageal reflux (as defined in the protocol); * failure to thrive; * intrauterine growth restriction; * hematochezia; * significant diarrhea or fever ≥38 °C; * congenital heart disease, immunodeficiency, asplenia, malignancy, cystic fibrosis or liver disease; * probiotic or systemic/oral antibiotic use in the 7 days before screening or anticipated use during the study; * use of treatments for infantile colic; including proton pump inhibitors; in the 7 days before screening or during the study. * Infant and mother must not participate concurrently in another interventional clinical study.