Constipation is characterized by difficult or irregular bowel movements. You may be constipated if you experience hard stools, infrequent – fewer than three per week – stools, straining during bowel movements or the sensation of incomplete defecation. Karo syrup is a brand of corn syrup. Mayo Clinic pediatrician Jay L. Hoecker says it was once a popular home remedy for constipation in infants.
Karo syrup is a concentrated solution of glucose and other sugars derived from corn starch. It has a mild, sweet taste and a thick consistency. It comes in three varieties, including light, lite and dark. "Light" refers to color while "lite" refers to calorie content. Karo dark corn syrup also contains refiner’s syrup, a type of molasses. This is the type of corn syrup Hoecker says was traditionally used to treat constipation.
Hoecker says that older versions of dark corn syrup contained significant amounts of a sugar alcohol called sorbitol that draws fluid into the intestine, producing a laxative effective. However, Hoecker questions whether modern commercial processing methods generate enough sorbitol to be effective. The Karo Syrup website reports only glucose content -- 15 to 20 percent -- and describes the rest of its components as “a mixture of various other types of sugar.”
As of November 2010, the National Library of Medicine lists no studies evaluating the effectiveness of Karo or other corn syrups for treating constipation. In the "Parents' Common Sense Encyclopedia," pediatrician Jeffrey W. Hull describes Karo syrup as his “first choice recommendation” for treating constipation in bottle-fed infants and says “it almost always works, if used properly.” However, Hull says, most doctors don’t use it correctly, which is why they obtain poor results. For best results, Hull says parents should add 2 tsp. per bottle of formula.
Hoecker cautions that corn syrups, such as Karo, may contain botulism spores. In children younger than 1, these spores can survive in the gastrointestinal tract and cause a rare, but serious, form of food poisoning. However, Hull points to a September 2003 report published in the journal “Clinical Pediatric Emergency Medicine,” that concluded corn syrup is "no longer a risk factor for infant botulism because of a recent change in the processing formula."
Experts disagree on the safety and effectiveness of using Karo syrup for constipation. Before you use it on your child, talk to the child's doctor. Your doctor may suggest other strategies. For example, Hoecker suggests offering 2 to 4 oz. of prune, pear or apple juice and replacing rice cereal with barley cereal. Hoecker says you can also apply a small amount of water-soluble lubricant to your child's anus. Never use mineral oil, laxatives or enemas on any child, except as directed by the child’s doctor. If constipation persists or the child develops other symptoms, such as vomiting or irritability, contact the child’s doctor for further instructions.