For centuries parents have coped with babies who are fussier than they should be. With no way to know what was going on, many parents and their doctors gave up on trying to heal them and simply tried to cope with them. The term "colic" was gladly accepted by overwhelmed doctors as a diagnosis for these inexplicably unhappy babies. Unfortunately, a diagnosis of colic sentenced baby and parents to weeks or months of inconsolable crying. Even the best parent can fall apart under those circumstances.

Colic is A Symptom, Not a Sickness
Fortunately, we live in an age when the human body is not such a mystery. We can peek inside, find out how it works, and discover whether it's working properly or not. Modern medical advances have made coping with your colicky baby a brighter prospect, because we now know that real problems lie behind all the screaming and something can be done about them.
Even the pickiest of babies won't cry for no reason. One reason behind many cases of chronically cranky babies is cows' milk allergy. Allergies cause many uncomfortable symptoms, any one of which might make baby cry. Particularly unhappy babies may have a condition called MFPI (multiple food protein intolerance.) The bad news is that allergies are as yet incurable. The good news is your baby's allergies can be managed and almost all babies eventually grow out of them. By eliminating allergens from baby's diet, you can rediscover your baby's cheerful personality.
The Burps and Bumps of Allergies
Allergies occur because the immune system mistakenly identifies harmless substances as hazards and tries to fight them off, so allergy symptoms resemble an illness. Symptoms can either show up immediately after eating an allergenic food as rapid-onset symptoms or hours or days later as delayed-onset symptoms. Symptoms include rashes (such as hives, eczema, or diaper rash,) vomiting or excessive spitting up, irritability, congestion, diarrhea, and blood in the stool.
In infants, especially breastfed babies, the symptoms are usually delayed. Often the symptoms will start out mild and increase as the baby's body builds up an allergy to a food. This can start at birth, or any time thereafter. Symptoms are frequently passed off as illness, so consider the possibility of allergies any time your baby has a low-grade chronic health problem, such as a slight cold that never goes away or a permanent case of diarrhea.
Both breastfed and formula-fed babies can experience food allergies. Formula-fed infants can react to the milk ingredients in formula and breastfed babies can show intolerance to any food mama eats. The most common foods breastfed infants react to are dairy (milk products,) chocolate, spices, caffeine, broccoli, and wheat. Additionally, many babies who are allergic to milk are also allergic to soy.
What to Do For Babies with Food Allergies
If you see symptoms of allergies in your infant consult your pediatrician. Your doctor will most likely prescribe an elimination diet or may order lab tests to determine the food your baby is allergic to. The elimination diet is the preferred method for many doctors and parents since allergy testing is uncomfortable and frequently inaccurate. Plus, the allergenic food will have to be eliminated from baby's diet anyway, so using elimination to discover the offending food serves two purposes at once. If you don't want to wait until you can get in to see the doctor, it's perfectly safe to try the elimination diet on your own and can even help you provide better information to your doctor.
Elimination diet for formula-fed babies
For formula-fed babies, the elimination diet is quite simple: just change formulas. But which formula should you change to? The obvious switch is to soy formula, since most babies are sensitive to cows' milk, but this isn't always the best answer. Babies who are sensitive to milk are more prone to be allergic to soy as well, so you might not see any improvement in your infant by switching to soy.
Hypoallergenic formulas are much more likely to solve the problem, though they are much more expensive than regular formula. The milk proteins in hypoallergenic formulas have been broken down a little to make them less recognizable to baby's digestive system. When even these formulas don't work, super hypoallergenic formulas are the only other alternative. Babies who suffer from MFPI (see below) usually need these special formulas.
It's important to note that babies will not respond to a formula switch immediately. It can take from a few days to a couple weeks for the irritating milk proteins to leave the system. You should wait at least a week before determining whether a formula is helping or not. By then baby should show some sign of improvement, but will probably need a little more time before the full effect can be determined.