The aim of this clinical trial is to assess the impact of B. lactis B94 on participants with infantile colic. It is hypothesized that participants given the probiotic formula will have a significant reduction in their crying duration compared to participants receiving the placebo, after 4 weeks of intervention.

The goal of this clinical trial is to evaluate the potential beneficial effects of B. lactis B94 on the symptoms of infantile colic.

Participants diagnosed with infantile colic will be recruited to participate in this randomized, double-blind, placebo controlled, two-armed parallel study. Eligible participants will be enrolled in this study for 6 weeks, and will undergo a 1-week run-in baseline period followed by a 4-week interventional period, then a 1-week follow-up period.

The study will consist of 3 in-person visits and 4 phone calls.

Inclusion Criteria:

I1. Healthy male or female. I2. Age ≤ 8 weeks old. I3. Diagnosis of infantile colic according to the Rome IV criteria. Infants must show cry or fuss behavior for 3 or more hours per day, during 3 or more days in 7 days.

I4. Exclusively breastfeeding and planning to breastfeed for the duration of the study.

I5. With a written informed consent signed by the father and mother or legal guardian.

I6. With parents willing to complete questionnaires, records, and diaries associated to the study and to complete all clinical visits and scheduled telephone calls.

I7. At least one of the legal representatives is affiliated with a social security scheme.

Exclusion Criteria:

E1. Birthweight < 2500 g. E2. Gestational age < 37 weeks. E3. Apgar score at 5 minutes < 7. E4. Partially or fully formula fed infants except for the 4 first days after birth.

E5. Stunted growth/weight loss (< 100 g/week from birth to last reported). E6. Gastroesophageal reflux disease, short bowel syndrome, chronic intestinal diseases, or gastrointestinal malformations.

E7. Diagnosed or reported fever and/or infectious diseases, or current systemic infections, or history of congenital infections.

E8. Genetic diseases and chromosomal abnormalities. E9. Metabolic diseases or pancreatic insufficiency. E10. Immunodeficiency. E11. Neurological diseases. E12. Suspected or confirmed food allergies and intolerances. E13. Mother who consumed antacid medications (proton pump inhibitor and H2 receptor antagonist) within the month before birth and intend to consume any during the trial.

E14. Use of probiotics, prebiotics, antibiotics, or gastric acid inhibitors by the infant at any time from birth to the moment of screening and during the trial.

E15. Use of anti-colic medication at any time from birth to the moment of screening.

E16. Use of probiotics and prebiotics supplements by the mother between the birth of their infant and the moment of screening and intend to consume any during the trial.

E17. Currently enrolled in another clinical study or having participated in another clinical from birth to the moment of screening.

E18. Whose legal representatives have psychological or linguistic incapability to sign the informed consent.

E19. Impossibility to contact the legal representatives in case of emergency.