Red stool, and other “abnormal” stool colors reviewed

Stools can come in many different colors and shades, most of which are normal.  However, the typical or “normal” stool are any shade of brown, tan, yellow, or green.  Most unusual stool colors are caused by food color, including artificial additives and colors.  This is especially true with diarrhea when the food passes through the child’s system much faster.  The only stool colors that are potentially abnormal or concerning are red, black, and white.

Red stool:

Up to 90% of red stool is not from blood.

Food is still the most common cause of red stools, including foods like Jello, red drinks (Kool-Aid), candy, frosting, food coloring, beets, red peppers, rhubarb, tomatoes (including juice, soup, sauce), cranberries.

Medications can also cause red stools with amoxicillin and cefdinir (orange/red color) being the most common in children.

Lower Gastrointestinal Blood – Some common causes include anal fissures from constipation, milk protein intolerance in infants, and swallowed maternal blood in newborns.  Other possible causes include infections or inflammatory bowel disease.

Black Stool:

Foods such as Oreos, grape juice, licorice, or others with black food coloring.

Medications, especially iron or Pepto Bismol.

Blood from the Stomach – The acid in the stomach turns blood black causing black stool.

A common cause of this in children is swallowed blood from a nosebleed.  Other causes would include stomach or esophageal ulcers.

Dark green stools are completely normal but can often appear black at first look.  If you are unsure, smear a small amount on a white tissue and hold it up under a bright light to differentiate dark green from black stool.

Call your pediatrician or seek care right away if your child has red or black stool along with, diarrhea, abdominal pain, vomiting, fevers, pale appearance, they are acting weak or sick or if there is a large amount of bright red blood present, as these may be a sign of a more severe medical problem.

White or light grey:

Babies with blockages in their bile ducts from a rare but very serious liver disease will have light gray, white, or very light-yellow stools.

White stool can also be the result of a milk only diet or some medications such as barium enemas (which are used in hospitals only) and some antacids.

See your pediatrician if your newborn or infant has very light grey or light yellow, or white stools more than once or twice.  

Tips for what to do if you are unsure or concerned about stool color:

• Save a sample to show your pediatrician or take a photo if unable to bring a sample.
• Review all foods and medications ingested within the previous 24-48 hours.
• Remove any possible causes mentioned above, such as foods or medications that aren’t necessary.
• Call your pediatrician if no cause is identified, if color does not improve after removing a possible cause, or if any of the above-mentioned symptoms develop.

If you have questions about your child’s stool when their pediatrician’s office is closed, book a telemedicine appointment.

Resources:

The Many Colors of Baby Poop

Stool – Unusual Color: Symptoms Checker