K591 - Ongoing diarrhea without an identifiable medical cause

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

Functional diarrhea is a condition where you experience frequent loose or watery bowel movements (at least 3 times per day) for an extended period, but medical tests cannot find a specific disease or infection causing it. Unlike other digestive conditions, there's no inflammation, infection, or structural problem in your intestines. The diarrhea occurs due to how your digestive system functions rather than from a specific illness. This condition can be chronic (long-lasting) and may be related to factors like stress, diet, or how your intestines process food and fluids. It's diagnosed when other causes have been ruled out through appropriate testing.

Additional Information

This diagnosis is typically made after excluding other causes of diarrhea. Treatment focuses on symptom management and lifestyle modifications. The associated lab test suggests ongoing monitoring or evaluation of the condition.

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 rule out other causes
  • Symptom duration assessment
  • Possible stool tests or other diagnostic procedures

What to Expect After

  • Dietary modifications
  • Stress management
  • Regular monitoring of symptoms
  • Possible medication management
  • Follow-up appointments with healthcare provider

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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