ICD-10 K58.9
Billable / SpecificIrritable bowel syndrome, unspecified
About ICD-10-CM K58.9
ICD-10-CM code K58.9 represents Irritable bowel syndrome, unspecified. This is a billable/specific code in the Digestive System chapter (block K58). The 2026 edition of ICD-10-CM K58.9 became effective on October 1, 2025.
Inclusion Terms / Approximate Synonyms
Clinical terms and conditions classified under K58.9. Per CMS ICD-10-CM Tabular 2026.
- Irritable bowel syndrome NOS
Medicare LCD Coverage for K58.9
Local Coverage Determinations (LCDs) from CMS MACs that list K58.9 as a covered diagnosis.
Showing top 10 of 168 total . Click a CPT for full coverage scope.
Commercial Payer Coverage
Coverage policies from major commercial payers referencing K58.9.
5 Medicare
1 Aetna
CPT Codes Commonly Billed with K58.9
Procedures frequently paired with this diagnosis based on PayerReady's Dx↔Px linkage data.
- 99204 New patient office visit — multiple chronic conditions: HTN, T2DM, hyperlipidemia, asthma, anxiety, depression, obesity, IBS, COPD, thyroid, anemia, CAD, sleep apnea, psoriasis, RA Primary Care
- 99214 Established patient — moderate complexity: uncontrolled HTN, diabetes with complications, multiple chronic conditions, COPD, AFib, CKD, sleep apnea, chronic pain, depression Primary Care
- 45378 Diagnostic colonoscopy — colorectal screening, family hx colon cancer, polyp, melena, iron def anemia, diverticulosis, ulcerative colitis, Crohn, occult blood, rectal polyp, weight loss, IBS Gastroenterology
Convert K58.9 to ICD-9-CM
Per CMS General Equivalence Mappings (GEMs), useful for legacy data review and historical claim analysis.
| ICD-10 | ICD-9 | Mapping Flags |
|---|---|---|
| K58.9 | 5641 | 10000 |
Flags format (5 digits): Approximate · No Map · Combination · Scenario · Choice List. Source: CMS 2017 GEMs (final version).
Codes Adjacent To K58.9
Other codes in section K55-K64 (Other diseases of intestines).
ICD-10 K58.9, Billing FAQ
Is ICD-10 code K58.9 billable? +
Yes, K58.9 is a billable ICD-10-CM code that can appear as a primary or secondary diagnosis on claims.
What other names or terms map to K58.9? +
ICD-10 K58.9 includes: Irritable bowel syndrome NOS.
What CPT codes are commonly billed with K58.9? +
Procedures frequently paired with K58.9 include: 99204, 99214, 45378.
What ICD-9 codes does K58.9 map to? +
Per CMS GEMs, K58.9 maps to ICD-9 codes: 5641. Useful for legacy data review and historical claim analysis.
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Reviewed by the PayerReady Medical Coding Team
Verified against the CMS 2026 code set on July 16, 2026.
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