What causes stool odor?

Many different diseases, disorders and conditions can lead to foul-smelling stools. Foul-smelling stools can be a sign of inflammatory disorders, intestinal infections, malabsorption disorders, and inherited medical conditions.

Infectious causes of stool odor

Foul-smelling stools may arise from intestinal infections caused by viruses, bacteria and parasites including:

  • Clostridium difficile bacteria

  • Cryptosporidium parasites

  • E. coli bacteria

  • Giardia parasites

  • Salmonella bacteria

  • Shigella bacteria

Inflammatory causes of stool odor

Inflammatory causes of foul-smelling stools include:

Malabsorptive causes of stool odor

Foul-smelling stools may arise from malabsorption disorders in which your body does not absorb nutrients from food efficiently. Malabsorption disorders include:

  • Celiac disease (severe sensitivity to gluten from wheat and other grains that causes intestinal damage)

  • Short bowel syndrome (nutrients are not absorbed due to intestinal disease or surgery)

Inherited causes of stool odor

Foul-smelling stool is one possible symptom of cystic fibrosis, which is an inherited condition that causes thick mucus buildup in the lungs and digestive tract. Although most people with the disease are diagnosed before age two, some people are not diagnosed until young adulthood.

Serious or life-threatening causes of stool odor

In some cases, foul-smelling stools may be a symptom of a serious or life-threatening condition that should be immediately evaluated in an emergency setting. These include:

  • Abdominal abscess

  • Intestinal obstruction

Questions for diagnosing the cause of stool odor

To diagnose the underlying cause of foul-smelling stool, your doctor or licensed healthcare provider may ask you several questions related to your symptoms. You can best help your healthcare provider in diagnosing the underlying cause of your stool odor by providing complete answers to these questions:

  • When did your stool odor start?

  • What color are your stools? Are they lighter or darker than normal?

  • Do you have difficulty pushing or moving your stools?

  • What is your current diet? Have you made any recent changes in your diet?

  • Do you notice a change in your stool odor with any particular foods or drinks?

  • What are your other symptoms?

Your healthcare provider may request a stool sample to help in diagnosing the underlying cause of your stool odor.

What are the potential complications of stool odor?

Complications of foul-smelling stool depend on the underlying disease, disorder or condition. Identifying and treating the underlying cause of stool odor is important to minimize any potential complications. Because foul-smelling stool can be due to serious diseases, failure to seek treatment can result in serious complications and permanent damage. Once the underlying cause is diagnosed, it is important for you to follow the treatment plan you and your healthcare professional design specifically for you to reduce the risk of potential complications including:

  • Dehydration due to a decreased desire to drink fluids

  • Loss of appetite

  • Poor nutrition due to a decreased desire to eat


What is stool odor?

Stool odor is the smell associated with stools, or bowel movements. Stools normally have an unpleasant odor.... Read more about stool odorintroduction


What other symptoms might occur with stool odor?

Foul-smelling stools may accompany other symptoms, which vary depending on the underlying disease, disorder or condition. Symptoms frequently affect the digestive tract but may also involve other body systems.... Read more about stool odorsymptoms

Medical Reviewer: McDonough, Brian MD Last Annual Review Date: Jul 8, 2011 Copyright: © Copyright 2011 Health Grades, Inc. All rights reserved. May not be reproduced or reprinted without permission from Health Grades, Inc. Use of this information is governed by the HealthGrades User Agreement.

This Article is Filed Under: Digestive System

Did You Know?

View Source

Half of those with IBS have symptoms before what age?