ICD-10 T78.41
Non-Billable HeaderArthus phenomenon
About ICD-10-CM T78.41
ICD-10-CM code T78.41 represents Arthus phenomenon. This is a non-billable header code in the Injury, Poisoning, and External Causes chapter (block T78). The 2026 edition of ICD-10-CM T78.41 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 Tips for T78.41
Specialist guidance from the PayerReady Medical Coding Team. Specificity warnings, HCC capture rules, sequencing notes.
Injury codes require a 7th character: A (initial encounter, active treatment), D (subsequent, healing/recovery), S (sequela, late effect of original injury). Codes with fewer than 6 characters need the placeholder X to bring them to 6 characters before adding the 7th. Wrong or missing 7th character is the #1 cause of injury claim denials.
Inclusion Terms / Approximate Synonyms
Clinical terms and conditions classified under T78.41. Per CMS ICD-10-CM Tabular 2026.
- Arthus reaction
Medicare LCD Coverage for T78.41
Local Coverage Determinations (LCDs) from CMS MACs that list T78.41 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 T78.41.
Our payer policy database covers Aetna, Cigna, Anthem, BCBS, Humana, and Medicare Advantage plans, but T78.41 doesn't currently appear in any indexed policy. The code may still be covered under standard plan benefits.
CPT Codes Commonly Billed with T78.41
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 T78.41
Other codes in section T66-T78 (Other and unspecified effects of external causes).
ICD-10 T78.41, Billing FAQ
Is ICD-10 code T78.41 billable? +
No, T78.41 is a non-billable header code. Use a more specific child code from block T78 when submitting claims.
What other names or terms map to T78.41? +
ICD-10 T78.41 includes: Arthus reaction.
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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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