ICD-10 R40.21
Non-Billable HeaderComa scale, eyes open
About ICD-10-CM R40.21
ICD-10-CM code R40.21 represents Coma scale, eyes open. This is a non-billable header code in the Symptoms, Signs, and Abnormal Findings chapter (block R40). The 2026 edition of ICD-10-CM R40.21 became effective on October 1, 2025. Non-billable codes cannot be used as a primary or secondary diagnosis on a claim, use a more specific child code instead.
Coding Notes
Seven Chr Note
- The following appropriate 7th character is to be added to subcategory R40.21-:
Medicare LCD Coverage for R40.21
Local Coverage Determinations (LCDs) from CMS MACs that list R40.21 as a covered diagnosis.
This doesn't mean the code isn't covered, it means no MAC has issued a Local Coverage Determination naming this specific code. Coverage may still apply under National Coverage Determinations or general medical-necessity rules.
Commercial Payer Coverage
Coverage policies from major commercial payers referencing R40.21.
Our payer policy database covers Aetna, Cigna, Anthem, BCBS, Humana, and Medicare Advantage plans, but R40.21 doesn't currently appear in any indexed policy. The code may still be covered under standard plan benefits.
CPT Codes Commonly Billed with R40.21
Procedures frequently paired with this diagnosis based on PayerReady's Dx↔Px linkage data.
We don't have CPT pairings indexed for this specific code yet. Use the CPT search above to find common procedures, or check your payer's published medical policy for code-specific guidance.
Codes Adjacent To R40.21
Other codes in section R40-R46 (Symptoms and signs involving cognition, perception, emotional state and behavior).
ICD-10 R40.21, Billing FAQ
Is ICD-10 code R40.21 billable? +
No, R40.21 is a non-billable header code. Use a more specific child code from block R40 when submitting claims.
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Reviewed by the PayerReady Medical Coding Team
Verified against the CMS 2026 code set on May 31, 2026.
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