Baby Probiotics: When and Whether to Use Them
The short answer
Probiotics are live beneficial bacteria that may help with specific infant digestive issues, but the evidence is mixed and their use should generally be discussed with your pediatrician. The strongest evidence supports Lactobacillus reuteri DSM 17938 for reducing crying time in breastfed infants with colic — a 2018 meta-analysis in Pediatrics found it reduced crying by about 50 minutes per day compared to placebo. Evidence for constipation and diarrhea prevention is less robust. The AAP has not issued a blanket recommendation for routine probiotic use in healthy infants, citing the need for more research on strain-specific effects, optimal dosing, and long-term safety. Probiotics should not be given to premature infants or immunocompromised babies without medical supervision.
Parents everywhere have the same worry. You are doing the right thing by looking into it.
By Age
What to expect by age
0-3 months
This is the peak period for infant colic, and where probiotic research is strongest. Lactobacillus reuteri DSM 17938 has the best evidence for breastfed colicky infants, with multiple randomized controlled trials showing benefit. The typical dose studied is 10⁸ CFU (100 million colony-forming units) daily. Evidence in formula-fed colicky infants is less clear. Always consult your pediatrician before starting any probiotic in a young infant.
3-6 months
As colic typically resolves by 3-4 months, the primary reason to consider probiotics may shift. Some pediatricians recommend probiotics during or after antibiotic use to help restore gut flora, though evidence specifically in this age group is limited. If your baby had colic and benefited from probiotics, your doctor may suggest continuing or tapering off.
6-12 months
With the introduction of solid foods, the gut microbiome undergoes significant changes naturally. Some parents consider probiotics to ease the digestive transition. Limited evidence suggests certain strains may help with acute gastroenteritis (stomach bug) duration, reducing diarrheal illness by about 1 day according to a Cochrane review. Probiotic-containing foods like yogurt can be introduced around 6 months.
12-24 months
Toddlers develop a more diverse gut microbiome through varied diet. Probiotic supplementation is generally unnecessary for healthy toddlers eating a balanced diet. Situations where a pediatrician might recommend probiotics include recurrent diarrheal illness, during antibiotic courses, or specific GI conditions like irritable bowel symptoms.
What Should You Do?
When to take action
- Choosing not to give your baby probiotics — they are not required for healthy infants
- Baby having gas, occasional fussiness, or stool changes without probiotics
- Your pediatrician suggesting a wait-and-see approach rather than recommending probiotics
- Mild gas or temporary stool changes when first starting a probiotic
- You are considering starting a probiotic and want guidance on appropriate strains and dosing
- Baby has colic (crying more than 3 hours/day, 3 days/week) and you want to discuss probiotic options
- Baby is on antibiotics and you want to discuss whether probiotics might help prevent diarrhea
- Baby has recurrent digestive issues like constipation or loose stools
- Baby develops a rash, hives, or breathing difficulty after taking a probiotic — this could indicate an allergic reaction
- Premature or immunocompromised baby develops fever, bloating, or feeding intolerance while on probiotics
- Baby has bloody stools, high fever, or signs of serious infection while taking any supplement
Sources
Related Resources
Trust your instincts. If something feels wrong, reach out to your pediatrician.
Worrying about your baby means you care. That is a good thing.
Related Digestive Concerns
Gas Relief Drops (Simethicone) for Baby
Simethicone gas drops (brand names Mylicon, Little Remedies Gas Relief) are safe for babies and work by breaking up gas bubbles in the stomach, making them easier to pass. They are not absorbed into the body. While they are very safe, research shows mixed evidence on whether they significantly reduce gas symptoms compared to placebo. They are worth trying but do not work for all babies.
Baby Constipation
Constipation in babies is defined by hard, dry, difficult-to-pass stools rather than by how often your baby poops. Breastfed babies can go several days without a bowel movement and still be perfectly normal. If your baby is passing soft stools comfortably, even if infrequently, they are likely not constipated.
Antibiotic-Associated Diarrhea in Baby
Diarrhea during or after antibiotic use is very common in babies because antibiotics kill beneficial gut bacteria along with the infection-causing ones. It typically resolves within a few days of completing the antibiotic course. Probiotics (particularly Saccharomyces boulardii or Lactobacillus) may help reduce antibiotic-associated diarrhea when given alongside the medication.
My Baby's Belly Looks Swollen
A rounded, slightly protruding belly is completely normal in babies and toddlers due to immature abdominal muscles and their proportionally larger organs. However, if the belly becomes suddenly swollen, feels hard and tight, or is accompanied by pain, vomiting, or changes in bowel movements, it needs medical evaluation as it could signal gas buildup, constipation, or rarely, something more serious.
My Baby Has an Anal Fissure (Blood When Pooping)
A small streak of bright red blood on the surface of your baby's stool or on the diaper is most commonly caused by an anal fissure, which is a tiny tear in the skin around the anus from passing hard stool. Anal fissures are very common in babies and toddlers and usually heal on their own with simple measures like keeping stools soft. While this is rarely serious, any blood in your baby's stool should be mentioned to your pediatrician.
Tummy Massage for Baby Gas
Gentle abdominal massage can help relieve gas and discomfort in babies by encouraging gas to move through the intestines. The technique involves gentle clockwise circular motions on the belly (following the direction of the digestive tract), the "I Love U" stroke pattern, and gentle knee-to-tummy movements. Massage also provides comforting touch that can soothe a fussy baby.