Researchers studies data from 14 previous studies that involved 1,927 children suffering from tummy problems like diarrhea, dehydration, constipation, abdominal pain and irritable bowel syndrome. But they couldn't find any conclusive result by combining these small studies. But a lot of studies did show that some herbal remedies do provide relief in case of certain gastrointestinal issues. For instance, four studies including 424 participants showed that remedies carob bean juice, and an herbal compound with chamomile may help with diarrhea. Another study with 120 participants indicates that peppermint oil can help curb chronic abdominal pain but it did not offer clear explanation for the same. The team of researchers believe that while it is possible that certain herbal medicines can prove to be helpful, parents should still consult a doctor before trying them out. Herbs might be safe but when combined with other compound they may have certain side effects and it is best to be cautious. 
Another reason for caution, according to Dr. Peter Lucassen, a researcher at Radboud University Medical Center in the Netherlands, is that although these small studies show that certain herbal remedies may work, they don't provide an explanation for how large the effects can be. Reiterating an earlier point made, the herbal medicines may use a combination of the main herb and other ingredients and you may not know how safe they are for your kids and they may also come with the risk of side effects and overdose. Therefore, it is best to consult a doctor before giving them to your kids as deciding to try herbal medicines without knowing whether they will work often leads to delayed diagnoses and may aggravate the ailment.
With inputs from Reuters