Allergic Colitis During Breastfeeding

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Babies who are 100% breastfed and have bloody stools may be allergic to milk. This does not mean that they're allergic to breastmilk. Instead, most often, they are allergic to the cow's milk proteins that are present in the milk and dairy products that their breastfeeding parent consumes. These are subsequently passed into breast milk.

Cow's milk proteins can trigger allergic colitis, which is the name for this condition of bloody stools. Colitis also can be triggered in infants when they are exposed (either in breast milk or formula) to proteins found in soy or goat's milk.

Allergic Colitis in Infants

Most food allergies are triggered by antibodies and cause immediate symptoms, like ​hives and difficulty breathing. In contrast, allergic colitis is a delayed-type hypersensitivity reaction. It occurs when milk proteins induce an inflammatory response in the intestine.

Signs and symptoms of allergic colitis often begin when infants are between the ages of two weeks and six months and might include the following:

  • Bloody stools
  • Diarrhea
  • Excessive gassiness
  • Some fussiness

The treatment is simply to remove whatever is triggering your child’s symptoms, which is usually cow’s milk proteins. After about three to four days, you should see the symptoms gradually improve.

Seek immediate medical attention if your child has more severe symptoms associated with bloody stools, including excessive fussiness, persistent vomiting, or fever.

Baby Formula and Allergic Colitis

Babies who are fed formula can also have allergic colitis because many forms of infant formula are based on cow's milk. A switch to a hypoallergenic formula, like Nutramigen Lipil or Alimentum, usually helps these babies. Because soy formula can also cause allergic colitis, a soy protein-based formula is not typically a good substitute. Your pediatrician can help you determine the best formula for your baby.

The guidelines are mixed on how long should babies stay on their new formula. Although some experts recommend continuing the hypoallergenic formula until 12 months, at which time you might slowly introduce cow's milk, others advise introducing a cow's milk-based formula even earlier, after the infant has been on the hypoallergenic formula for at least six months. Your doctor can guide you on this too.

For babies who can't tolerate Nutramigen or Alimentum, formulas made up of 100% free amino acids (meaning they are even easier for babies to digest) are also available, including Neocate, PurAmino, and EleCare.

Breastfeeding and Allergic Colitis

While babies with known or suspected allergic colitis receiving formula should switch to a more hypoallergenic formula, breastfed babies should continue breastfeeding. Their symptoms are usually relieved when breastfeeding parents eliminate milk and dairy products from their diets. Talk to your doctor about alternative sources of calcium, since drinking cow’s milk and soy milk is a common way for many people to get calcium in their diet.

Other foods can also trigger allergic colitis, and many foods can have hidden ingredients to which your baby might be allergic. In addition to milk and soy, other possible allergens include chocolate, citrus fruits, corn, eggs, nuts, peanuts, strawberries, and wheat. Keeping a food diary may help, and it will be important to read food labels and get extra help if this problem continues. Stopping breastfeeding is not recommended.

A pediatric gastroenterologist can help if your child with allergic colitis has severe symptoms, including weight loss, or if you are having trouble finding a diet that works. A very low-allergen elimination diet might be tried if nothing else is working. This would include only eating foods like chicken or lamb, pears, squash, and rice while breastfeeding, in addition to taking a multivitamin and mineral supplement.

Because this is a restrictive diet, a nutrition professional should be consulted to make sure you and your baby get adequate nutrition. Fortunately, allergic colitis is often temporary, with symptoms disappearing (when challenged) by the time your baby is about a year old.

Having bloody stools also can be caused by intestinal infections or from rectal tears, a common complication of being constipated. That makes it important to talk to your pediatrician if you think that your baby has allergic colitis to ensure they get a correct diagnosis and that an appropriate treatment plan is followed.

A Word From Verywell

Seeing blood in your baby's stool is alarming, and certainly, it's important to contact your doctor. However, in most cases, this condition is easily treated by eliminating milk products from your diet (if you are breastfeeding) or switching to a hypoallergenic formula.

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7 Sources
Verywell Family uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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