Your infant has been crying - a lot. That's what babies do. But how do you know if your baby has colic? I asked Dr. Charles Shubin, director of pediatrics at Mercy FamilyCare, a division of Family Health Centers of Baltimore, to provide today's Consult.

Colic, Shubin explained, is not a defined medical disease but a diagnosis that's made when doctors and parents have ruled out other reasons for a baby's discomfort. But here are some of the signs he said might lead you to talk to your pediatrician about colic: Your baby is 1 to 4 months of age; she cries for long periods at a time, after you've tried feeding her, burping her and changing her to help; and the extended crying has something of a daytime pattern that often occurs in the late afternoon and early evening. "They cry continuously or a lot, or they're not well-consolable," Shubin said.

What can you do if the doctor can't find a physical cause of discomfort and says your child does have colic? Shubin says some parents have had success swaddling the baby - wrapping her tightly in a blanket like a burrito, which you might have done when she was born. Vibrating baby chairs and swings might also calm the baby, but Shubin cautions that you shouldn't prop the infant on top of a clothes dryer - the vibrations might be soothing, but the baby could fall off.

The good news is that time is on a parent's side. Most babies stop extended crying about the time they learn to sleep through the night, about 4 months, Shubin said. If yours is still crying for hours every day much beyond that, it's time to talk to your doctor again.