In general, a baby is considered to have colic when he or she cries for more than three hours straight at least three days per week for more than three weeks, but is otherwise healthy. The causes of
colic in babies are not completely understood, and various factors may play a role.
Although it can be frustrating, and maybe even worrisome, colic will not last forever. Typically speaking, the condition peaks around six to eight weeks, and then goes away around the baby's third month. In many cases, it stops as mysteriously as it began.
(Click Infant Colic for more information, including the differences between normal crying and crying in a baby with colic, possible risk factors, and how the condition is diagnosed.)