Doctors define colic as 3 or more hours a day of continued crying. The crying is not due to hunger, a wet diaper, or other visible causes, and the child cannot be calmed down. Colic usually goes away by 3 months of age. A baby's fussiness may not be colic at all. The first thing to do is look for signs of illness.
Colicky babies have a healthy sucking reflex and a good appetite.
Sick babies may appear colicky but won't have the same strong sucking reflex, and they'll also drink less milk. Colicky babies like to be cuddled and handled. Colicky babies may spit up from time to time, but if your baby is actually vomiting , you should call the doctor. True vomiting is not a sign of colic. Doctors now believe that colic is rarely, if ever, caused by a milk allergy.