The Facts

• Diarrhea in a baby is the passage of excessive amounts of loose, watery stool. According to BabyCenter.com, a common cause of diarrhea in babies is food allergies, which occur when your little one develops a reaction to proteins in a particular type of food. (see reference 1)
  
  

Symptoms

• If your baby has diarrhea as a result of allergies, he may experience a range of other symptoms as well, including abdominal cramps, gas, bloody stool, hives and even breathing problems, such as anaphylactic shock, in some situations.
  
  

Common Causes

• The most common cause of allergy-related diarrhea in babies is milk. Other causes of allergy-related diarrhea include fish, peanuts, soy, eggs, wheat and tree nuts.
  
  

Diagnosis

• If your doctor suspects your baby's diarrhea is caused by allergies, he will assess your little one's symptoms and may ask you to conduct a food diary or eliminate foods from your baby's diet before conducting a skin or blood test to check for allergic reactions.
  
  

Misconceptions

• Many people confuse food allergies with food intolerance in babies. According to James Li, MD, an allergy and asthma specialist at the Mayo Clinic, food allergies--unlike food intolerance--typically involve your baby's immune system; with food allergies, your baby's body produces antibodies to fight a food it identifies as harmful, which makes the immune system produce histamines, ultimately causing allergy symptoms such as diarrhea. (see reference 2)