Non-Billable / Non-Specific Code
ICD-10-CM K63.821 is the diagnosis code for Small intestinal bacterial overgrowth. This code falls under the section "Other diseases of intestines" within Chapter 11 — Diseases of the digestive system (K00-K95). It is a non-billable/non-specific ICD-10-CM code that should not be used for reimbursement. A more specific sub-code is required for billing. Medical coders and healthcare providers use this code to document and classify diagnoses in electronic health records, insurance claims, and clinical databases.
Always refer to the official ICD-10-CM Tabular List for complete coding guidelines. Ensure documentation supports the specificity of the code selected. When in doubt, consult a certified medical coder or the latest CMS guidelines.
Understanding where K63.821 sits in the ICD-10-CM classification helps ensure proper coding:
No, K63.821 is a non-billable/non-specific code. You should use a more specific sub-code for billing and reimbursement.
K63.821 is the ICD-10-CM diagnosis code for "Small intestinal bacterial overgrowth". It is used by healthcare providers to classify and document this condition in medical records and insurance claims.
The parent code of K63.821 is K63.82 ("Intestinal microbial overgrowth"). K63.821 provides a more specific classification within this category.
K63.821 is located in Section K55-K64 — "Other diseases of intestines" within Chapter 11 of the ICD-10-CM Tabular List.
K63.821 has 3 sub-code(s) that provide more specific detail: K63.8211, K63.8212, K63.8219.
Use K63.821 when the patients documented diagnosis matches "Small intestinal bacterial overgrowth" and the clinical documentation supports this level of specificity. Always verify with the latest ICD-10-CM guidelines and payer requirements.
The ICD-10-CM code for Small intestinal bacterial overgrowth is K63.821.
No, K63.821 is non-billable. Use a more specific sub-code for primary diagnosis billing.
K63.821 is in Chapter 11 of the ICD-10-CM Tabular List.
Yes, K63.821 is a valid ICD-10-CM code for the 2026 fiscal year, subject to official CMS updates.