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The causes of baby diarrhea and constipation, and ways to help

Knowing what makes your baby feel uncomfortable might depend on whether her digestive system is in good working order. If she is not having regular bowel movements, she might be experiencing diarrhea or constipation. Learn how to recognize the symptoms of both and learn how you can help her feel better.

Baby diarrhea

Diarrhea can be caused by an infection, or your baby's inability to properly digest nutrients in her food. When your baby’s stool suddenly becomes softer and more frequent than what’s normal for her, she might have diarrhea.


When should you be concerned?

If the frequency and volume of diarrhea become excessive, or if you notice any of the following symptoms, call your pediatrician or health care professional:

  • Blood or mucus in stools
  • Fever
  • Vomiting
  • Irritability
  • Refusal to eat
  • Decreased or dark-colored urine
  • Decreased activity

What baby diarrhea treatment should you try?

If diarrhea persists or worsens, see or talk to your health care professional. Switching baby formulas might help. Similac Expert Care® for Diarrhea provides complete nutrition for the dietary management of diarrhea to help firm loose and watery stools in infants older than 6 months and toddlers.

Baby constipation

Several factors can lead to your baby becoming constipated, having difficulty passing stool, passing stool that is hard and dry, or having bowel movements less frequently than usual:

  • Eating solid foods for the first time can cause constipation. It is possible that some of the foods you feed your baby for the first time — such as rice cereal and oatmeal — don’t provide enough fiber to promote regular bowel movements.
  • Dehydration causes constipation. Her body, when not properly hydrated, absorbs fluids from whatever she eats and drinks, including fluid from the waste in her bowels.
  • Baby formulas contain palm olein oil. Breast milk contains a balanced amount of fat and protein to ensure good digestive health and development. Substitutes in baby formula, such as palm olein oil, can harden stools in some babies.
  • Illness or other medical conditions can disrupt healthy digestive functions. Some babies develop diseases, or have underlying medical conditions, that result in chronic constipation. Check with your doctor if your baby has difficulty passing stools.

How can you ease your baby's constipation?

Some doctors recommend adding 1 to 2 ounces of prune, apple, or pear juice to formula or breast milk. The sugar in these juices will help to loosen the stool. Exercise her legs to break up the hardened stools in her bowels, or gently massage her stomach if symptoms continue. Do not give your baby over-the-counter stool softeners unless advised by your pediatrician or health care professional.

Ask your health care professional about switching to a formula such as Similac® Advance®, which does not contain palm olein oil, an ingredient that can harden stools in some babies.

Bowel movements

The normal range for bowel movements in babies is vast. Infant stool varies from baby to baby, and from day to day. Stool can be yellow, green, or brown and still be considered normal. Normal consistency ranges from runny applesauce to playdough.

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