Babies who cry may simply be hungry, uncomfortable, or ill. Less than 10% of babies who would meet the definition of colic based on the amount they cry have an identifiable underlying disease.Cause for concern include: an elevated temperature, a history of breathing problems or a child who is not appropriately gaining weight.Indications that further investigations may be needed include:
Vomiting (vomit that is green or yellow, bloody or occurring more than five times a day)
Change in stool (constipation or diarrhea, especially with blood or mucous)
Abnormal temperature (a rectal temperature less than 97.0 °F (36.1 °C) or over 100.4 °F (38.0 °C)
Irritability (crying all day with few calm periods in between)
Lethargy (excess sleepiness, lack of smiles or interested gaze, weak sucking lasting over six hours)
Poor weight gain (gaining less than  15 grams a day)Problems to consider when the above are present include:
Infections (e.g. ear infection, urine infection, meningitis, appendicitis)
Intestinal pain (e.g. food allergy, acid reflux, constipation, intestinal blockage)
Trouble breathing (e.g. from a cold, excessive dust, congenital nasal blockage, oversized tongue)
Increased brain pressure (e.g. hematoma, hydrocephalus)
Skin pain  (e.g. a loose diaper pin, irritated rash, a hair wrapped around a toe)
Mouth pain (e.g. yeast infection)
Kidney pain  (e.g. blockage of the urinary system)
Eye pain (e.g. scratched cornea, glaucoma)
Overdose  (e.g. excessive Vitamin D, excessive sodium)
Others (e.g. migraine headache, heart failure, hyperthyroidism)Persistently fussy babies with poor weight gain, vomiting more than five times a day, or other significant feeding problems should be evaluated for other illnesses (e.g. urinary infection, intestinal obstruction, acid reflux).
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External links

Baby colic at Curlie