Narrowing of Stool

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Medically Reviewed By:

Aiko Yoshioka

Aiko Yoshioka, MD


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People with these symptoms also use Ubie's symptom checker to find possible causes

  • Smaller caliber stool

  • Narrow (thin) stools

  • Long and thin stool

  • Smaller caliber poo

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Content updated on Sep 6, 2022

About the symptom

Decrease in stool caliber describes a condition with thin narrow stools.

When to see a doctor

Seek professional care if you experience any of the following symptoms

  • Thin narrow stool

Possible causes

  • Colon cancer

    Cancer of the large intestines. It can be treated easily in the early stage, hence the general population is encouraged to go for screening with stool blood tests and colonoscopy (camera screening).

  • Rectal cancer

    Rectal cancer is cancer that begins in the rectum. Malignant, or cancerous cells form in the tissue of the rectum and can spread to other parts of your body.

  • Sigmoid colon cancer

    The sigmoid colon is the terminal portion of the large intestine/ colon before reaching the rectum. The exact cause of sigmoid colon cancer is unknown but the cancer begins when healthy cells in the colon develop changes (mutations) in their DNA. Risk factors include family history, certain hereditary cancer syndromes, diet, smoking and alcohol use.

  • GIST

Questions your doctor may ask about this symptom

Your doctor may ask these questions to check for this symptom

  • Has your stool become thin and narrow (like a pencil)?

  • Do you have a fever?

  • Is there blood in your stool?

  • Do you have hard stools or constipation recently?

  • Do you have nausea or vomiting?

Other Related Symptoms

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Medically Reviewed By:

Aiko Yoshioka

Aiko Yoshioka, MD


From our team of 50+ doctors

Just 3 minutes.
Developed by doctors.

Ubie is supervised by 50+ medical experts worldwide

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