ICD-10 T42.2X6
Non-Billable HeaderUnderdosing of succinimides and oxazolidinediones
About ICD-10-CM T42.2X6
ICD-10-CM code T42.2X6 represents Underdosing of succinimides and oxazolidinediones. This is a non-billable header code in the Injury, Poisoning, and External Causes chapter (block T42). The 2026 edition of ICD-10-CM T42.2X6 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 T42.2X6
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.
Medicare LCD Coverage for T42.2X6
Local Coverage Determinations (LCDs) from CMS MACs that list T42.2X6 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 T42.2X6.
Our payer policy database covers Aetna, Cigna, Anthem, BCBS, Humana, and Medicare Advantage plans, but T42.2X6 doesn't currently appear in any indexed policy. The code may still be covered under standard plan benefits.
CPT Codes Commonly Billed with T42.2X6
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 T42.2X6
Other codes in section T36-T50 (Poisoning by, adverse effect of and underdosing of drugs, medicaments and biological substances).
ICD-10 T42.2X6, Billing FAQ
Is ICD-10 code T42.2X6 billable? +
No, T42.2X6 is a non-billable header code. Use a more specific child code from block T42 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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