While some research has suggested that probiotics may be helpful for everything from protecting preemies from serious intestinal infections to heading off eczema in older kids, other studies have not found a clear benefit. “We are a long way from being able to say, ‘Take this type of probiotic for this condition,’” says Dr. Kemper. “For now, if your child needs to take an antibiotic, talk to your doctor about choosing one with the narrowest spectrum possible so you don’t kill off the good bacteria with the bad.” If you want to try L. reuteri for your own fussy breastfed baby, talk to your pediatrician. The study found no harm from the treatment, so it may be worth a try.