Taking Montelukast correctly in newborns usually causes no harm, and there may be some adverse reactions, such as causing constipation. Montelukast is a more commonly used antidiarrheal drug, commonly used in the treatment of acute and chronic diarrhea in children and adults. This drug is more absorbent, and newborns can take montelukast on medical advice if necessary. The mucous membrane of the digestive tract has a certain protective effect, and has the effect of astringency, so as to play the effect of diarrhea, generally no serious harm. However, if newborns take too much montelukast, there may be some adverse reactions, the most common is that it may lead to constipation, thus constipation phenomenon. Newborns need to be careful with medication. If your newborn has diarrhea, do not give your newborn Montelukast privately. You need to seek medical attention and take medication under medical supervision if necessary.