Ten per cent of newborn children in the Western world experience colic.1 2 The aetiology is unclear but gastrointestinal factors and allergy to cow's milk protein have been suggested as possible causes.3 Another suggestion is that colic is a behavioural condition resulting from unfavourable parent–infant interaction.
By Apekshababy (Own work) [CC BY-SA 4.0 (http://creativecommons.org/licenses/by-sa/4.0)], via Wikimedia Commons