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Abnormal-Looking Stool

What causes abnormal-looking stool?

Toddler toilet training

Most changes in a child’s stool (feces) are due to a change in diet. Changes in diet may cause changes in:

  • colour
  • smell
  • consistency
  • amount of stool

Many medicines can affect what stool looks like. If your baby or child is taking medication, ask your pharmacist if you should expect a change in stool. Some changes that last more than a few days may require medical attention.

Brightly-coloured stool

Breast-fed babies usually produce a mustard-yellow coloured stool. They may also produce green, runny stool. This is normal. It should not be a concern.

In older babies and children, green, runny stool is usually a sign of gastroenteritis. This is also called “stomach flu”. Your child may need to see a doctor.

Pale stool

Whitish, light-coloured stool may be a sign of a bile duct blockage.

Floating and foul-smelling stools can be a sign of malabsorption. Malabsorption is when the digestive system does not absorb nutrients adequately. It may occur if your child has intolerance to, a digestive problem with, or an allergy to a certain food.

If your child has pale stool with yellowish skin and eyes or dark urine, they may have hepatitis​. See a doctor right away.

Bloody stool

Small amounts of fresh blood are common in children who are constipated and straining when passing stool.

Bloody, slimy, or mucusy stool may be a sign of infection. It may also mean inflammation of the large intestine or rectum.

If your baby or child’s stool has a red, jelly-like appearance, see a doctor right away. Make sure to tell your doctor if your child also has severe stomach pain and a pale complexion. This type of stool may be caused by intestinal obstruction.

Children with bloody stool may be suffering from inflammatory bowel disease.

When to see a doctor

Make an appointment with your child’s doctor if:

  • your child seems sick and the stool does not return to its normal colour in a few days
  • your child has blood in the stool and constipation is not the reason
  • your child’s stool continues to be very pale
  • your baby has green, runny stool and seems sick with other symptoms
  • your baby has green, runny stool but he is bottle-fed only

See a doctor right away, or go to the nearest Emergency Department, if:

  • your baby or child has red and jelly-like stool. Do not give your child anything to eat or drink while waiting for the ambulance
  • your child has yellowish skin or yellowish whites of the eyes
  • your child has dark urine (brown or black in colour)
  • your child’s stool is an abnormal colour after taking medication

Key points

  • Most changes in stool are due to a change in diet.
  • Runny green or mustard-coloured stool is common in breast-fed babies.
  • Pale stool accompanied by yellowish skin and eyes or dark urine may indicate hepatitis. Seek medical attention right away.
  • Red and jelly-like stool is considered an emergency. Call 911 or go to the nearest Emergency Department. Do not give your child anything to eat or drink while waiting for the ambulance.
  • Small amounts of blood lining the stool are common in children who are constipated. This is not an emergency.

Mark Feldman, MD, FRCPC

10/14/2010




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