What causes acholic stools (grey stools)?

Medical Advisory BoardAll articles are reviewed for accuracy by our Medical Advisory Board
Educational purpose only • Exercise caution as content is pending human review
Article Review Status
Submitted
Under Review
Approved

Last updated: April 3, 2025View editorial policy

Personalize

Help us tailor your experience

Which best describes you? Your choice helps us use language that's most understandable for you.

Differential Diagnosis for Grey Stools

  • Single most likely diagnosis
    • Biliary obstruction: This is the most likely diagnosis because grey stools are often associated with a lack of bile pigments, which are responsible for the normal brown color of stool. Biliary obstruction can prevent bile from reaching the intestines, resulting in grey or clay-colored stools.
  • Other Likely diagnoses
    • Pancreatic insufficiency: This condition can lead to malabsorption of fats and fat-soluble vitamins, resulting in pale or grey stools.
    • Liver disease: Certain liver conditions, such as cirrhosis or liver failure, can affect bile production and result in grey stools.
    • Medication side effects: Some medications, such as antacids or antibiotics, can cause changes in stool color, including grey stools.
  • Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
    • Hemorrhage: Although less likely, a massive gastrointestinal hemorrhage can cause grey or black stools (melena) due to the digestion of blood.
    • Intestinal ischemia: Reduced blood flow to the intestines can cause changes in stool color, including grey stools, and is a medical emergency.
  • Rare diagnoses
    • Gilbert's syndrome: A rare genetic disorder that affects the liver's ability to process bilirubin, resulting in pale or grey stools.
    • Dubin-Johnson syndrome: A rare genetic disorder that affects the liver's ability to transport bilirubin, resulting in chronic jaundice and grey stools.
    • Primary biliary cirrhosis: A rare autoimmune disease that affects the bile ducts and can cause changes in stool color, including grey stools.

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

Have a follow-up question?

Our Medical A.I. is used by practicing medical doctors at top research institutions around the world. Ask any follow up question and get world-class guideline-backed answers instantly.