What causes infantile colic?

While the cause of colic has not been established, there are several different factors that may contribute. These include gastrointestinal factors (such as gut flora, food intolerances, feeding frequency, inflammation and gastrointestinal immaturity), neurodevelopmental factors (such as increased intestinal motility), and drug-based factors (such as maternal smoking). Interactions between some of these factors are likely as well.^[1][2]