K921 - Black, tarry stools containing blood from upper digestive tract bleeding

International Classification of Diseases

Last updated: 10/3/2025

What is a ICD-10 Code?

ICD-10 (International Classification of Diseases, 10th Revision) codes are used to classify and code all diagnoses, symptoms, and procedures recorded in association with hospital care. These codes provide a standardized way to track health conditions and their treatment outcomes.

Detailed Description

Melena refers to black, tarry, sticky stools that have a distinctive foul odor. This condition occurs when blood from the upper part of the digestive system (such as the stomach or small intestine) is digested as it passes through the intestines, turning the stool dark black. The blood has been partially digested by stomach acid and enzymes, which gives it this characteristic appearance. This is different from bright red blood in stool, which typically comes from lower in the digestive tract. Melena is always considered a sign that needs medical attention as it indicates bleeding somewhere in the upper digestive system.

Additional Information

This code specifically identifies the symptom of melena (black tarry stools) but does not indicate the underlying cause of the bleeding. Additional codes would be needed to identify the source of bleeding.

Category

Digestive System Disorders

Medical Specialty

Gastroenterology

Expected Costs

Your actual cost will depend on your insurance coverage, provider location, and specific circumstances.

What's Required Before This

  • Medical evaluation to determine bleeding source
  • Often requires urgent medical attention

What to Expect After

  • Monitoring for continued bleeding
  • Treatment of underlying cause
  • Possible endoscopic evaluation
  • Blood work monitoring

Why Understanding This Code Matters

On Your Medical Bill

This code appears on your medical bills to identify the specific service, procedure, drug, or medical diagnosis you received. Understanding what it means helps you verify you're being charged correctly and know what to expect.

For Your Health

Knowing what this code represents helps you understand your treatment plan, ask better questions during appointments, and track your healthcare journey more effectively.

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