The mere thought of a colicky baby is often enough to strike fear in the heart of the parents of a newborn child. A baby with colic may cry for hours despite the parents' attempts at consolation; although the colicky phase will eventually end, it may seem like an eternity while it continues.

Colic is generally defined as excessive (frequently inconsolable) crying that lasts for more than three hours at least three days per week, continuing for at least three weeks; additionally, there must be no medical problem causing the crying.

Other symptoms frequently associated with colic include pulling the knees up towards the stomach, a hard and/or swollen stomach, and excessive gas. Crying occurs most often in the evening. Colic typically ends by the age of 4-5 months.

Colicky babies may be at an increased risk of abuse at the hands of exhausted and frustrated parents. Additionally, the parent may not properly bond with the child because of feelings of inadequacy and anger, leading to developing behavioral problems as the child grows.

No one knows for sure what causes colic, although there are many theories. One view attributes it to painful digestive cramps and/or excessive gas caused by allergic reaction to foods (such as milk). Another theory suggests that some babies may simply have a sensitive temperament, possibly compounded by a parental inability to respond to the infant's needs. Finally, what we call colic may just be an extreme version of normal infant crying, or an increased perception of normal crying by parents with less tolerance for it.

The antispasmodic and sedating drugs dicyclomine and dicycloverine appear to be effective for colic,1but they can have dangerous side effects in infants and are not recommended. The gas-relieving drug dimethicone is also sometimes recommended, but evidence suggests that it does not work.2

A number of natural approaches to colic have preliminary supporting evidence.

Fennel Seed Oil

In a double-blind, placebo-controlled study, 125 infants with colic were given either placebo or fennel seed oil at a dose of 12 mg daily per kg of body weight.48 The results were promising. About 40% of the infants receiving fennel showed relief of colic symptoms, as compared to only 14% in the placebo group, a significant difference. Another way to look at the results involves hours of inconsolable crying. In the treated group, infants cried about nine hours per week, compared to twelve hours in the placebo group.

While these are encouraging results, confirmation by an independent research group is necessary before the treatment can be accepted as effective. Furthermore, the safety of fennel seed oil for infants has not been conclusively established.

For more information, see the full fennel article.

Dietary Changes

Cow's milk can cause allergic reactions. Most infant formula contains cow’s milk, and can cause reactions in allergic babies. There is also some evidence that breast-fed infants may have allergic responses to cow’s milk proteins in the mother’s diet.3–7

Numerous small, open and double-blindstudies have evaluated the effects of cow's milk or cow’s milk protein in the diet of infants with colic.8–23,47Most (but not all) of these found an improvement in crying when cow's milk protein was removed from the diet of formula-fed infants, or from the diet of the mothers in breast-fed infants.24–31

As an alternative to standard cow’s milk–based formula, researchers primarily used hypoallergenic formula made from hydrolyzed (processed) whey or casein. Formula based on these sources of protein may be superior to those based on soy, because soy itself can cause allergic reactions in sensitive children.

If no improvement is seen through eliminating cow's milk, some experts recommend searching in the breastfeeding mother's diet for other potential food allergens, such as wheat, soy, or eggs.32–34 However, it is important to keep nutritional needs in mind: the nursing mother who eliminates certain foods needs to maintain an adequate intake of calcium, protein, and other nutrients.

It should be noted that most infants with colic are able to tolerate cow's milk protein as they get older, so neither the mother nor the baby are doomed to life without milk. Researchers propose that this might be the result of an immature digestive system; according to this theory, maturation of the digestive tract is the reason that colic usually disappears on its own in time.

Milk also contains lactose, a form of sugar that many adults can't digest (see the lactose intolerance article for more information). However, reducing the lactose content of infant formula has notbeen found helpful in treating colic.42

Probiotic Supplements

Probiotics are beneficial live intestinal bacteria. They may play a role in balancing bacteria in the gut, which may help relieve discomfort. Some, but not all, probiotics may be helpful for colic.

A randomized trial of 82 breastfed infants with colic compared supplementation with oral Lactobacillus reuteri (L. reuteri) to placebo for 21 days. A reduction in more that 50% in mean crying time was seen in all infants who received L. reuteri compared to 63% of infants in placebo group. L. reuterisupplement and was also associated with a larger decrease in the amount of daily crying and better family quality of life scores.54

In another randomized trial of 50 exclusively breastfed infants with colic, supplementation with L. reuterifor 21 days was associated with a 50% reduction in daily crying time when compared with placebo.57

A second randomized trial with 90 infants found a similar decrease in crying time with L. reuteri, but there were no significant differences in crying time found in a small trial of 18 infants when Lactobacillus rhamnosus and Propionibacterium freudenreichiiwere compared to placebo.55

L. reuteri was also found to have significantly better reduction in crying time compared to simethicone in randomized trial of 82 infants with colic. After 28 days, median crying time was reduced from 197 minutes a day to 51 minutes a day with L. reuteri supplemention compared to 145 minutes a day with simethicone. Crying time decreased by 50% or more in 95% of infants taking L. reutericompared to 7% of infants taking simethicone.56

Behavioral Methods

Many doctors believe that the cause of colic is not physical; rather, that it results from a child's oversensitivity to stimuli in the environment.36-40 Overanxious parents might contribute to the problem by adding more stimulation in an attempt to calm their child. Other parents might under-react in the belief that paying too much attention to the infant's cries will "spoil" him. Either response could set up a vicious cycle leading to long periods of inconsolable crying.

Based on these theories, some authorities recommend counseling the parents of a colicky infant on appropriate coping strategies, including building a personal support system and occasionally leaving the child with a different caregiver to provide a respite.

Studies evaluating the effects of carrying a colicky child more, or using a motion-simulation device, have not found benefit.41,42