T52.81 ICD-10-CM Code: Toxic effects of alkenes
Billing Status: NO. This is a clinician non-billable / parent hierarchy grouping in the ICD-10-CM system.
Code Set: New for FY2027 — not valid before October 1, 2026.
Official Registry Overview & Definition
Official Tabular Instructional Notes
Sequencing, inclusion, and exclusion notes published for T52.81 in the official ICD-10-CM tabular list.
Excludes1 — Not Coded Here
Conditions generally not reported together with this code (Excludes1) -- an error unless the two conditions are documented as unrelated to each other (ICD-10-CM Official Guidelines, Section I.A.12.a).
- halogen derivatives of aliphatic and aromatic hydrocarbons (T53.-) Compare T52.81 vs T53 →
- contact with and (suspected) exposure to toxic substances (Z77.-) Compare T52.81 vs Z77 →
Use Additional Code
Supplementary codes the tabular list directs you to add.
Frequently Compared Codes
The official Excludes notes on T52.81 name these codes. Each comparison page covers when the two can — or must not — be reported together.
Change history
- FY2027 — 2026-10-01Added to the code setToxic effects of alkenesFY2027 changes
Verify Before Coding
- Not billable as written — a more specific code is required: T52.811A, T52.811D, T52.811S, T52.812A, T52.812D.
- Requires a 7th character. "The appropriate 7th character is to be added to each code from category T52" Options: T52.811A, T52.811D, T52.811S, T52.812A, T52.812D, T52.812S
From the code registry, the Medicare Code Editor, and the MS-DRG Definitions Manual. Check it against a full claim.
Contextual Map
Every relationship of T52.81 in one view: hierarchy, official tabular instructions in both directions, clinical classification, risk adjustment, MS-DRG participation, index terms and change history — each edge carrying the CMS source it derives from.
Hierarchy
- S00-T88 — Chapter 19: Injury, Poisoning and Certain Other Consequences of External Causes (S00-T88) (S00-T88) [Hierarchy]
Nearest codes (40)
- T52 — Toxic effect of organic solvents [Sibling]
- T52.3X4S — Toxic effect of glycols, undetermined, sequela [Sibling]
- T52.4 — Toxic effects of ketones [Sibling]
- T52.4X — Toxic effects of ketones [Sibling]
- T52.4X1 — Toxic effect of ketones, accidental (unintentional) [Sibling]
- T52.4X1A — Toxic effect of ketones, accidental (unintentional), initial encounter [Sibling]
- T52.4X1D — Toxic effect of ketones, accidental (unintentional), subsequent encounter [Sibling]
- T52.4X1S — Toxic effect of ketones, accidental (unintentional), sequela [Sibling]
- and 32 more
Change history
- FY2027 — Added to the code set [Change history]
Frequently Asked Questions (FAQ) & Clinical Guidance
Can T52.81 be billed directly?
No. T52.81 (Toxic effects of alkenes) is a non-billable ICD-10-CM category code. A more specific billable subcode must be selected based on clinical documentation.
Does T52.81 require a 7th character?
Yes. The appropriate 7th character is to be added to each code from category T52.
Nearest Codes in This Family
Official ICD-10-CM classifications closest to T52.81 in its code family, with their registry titles.
- T52.4X4 — Toxic effect of ketones, undetermined
- T52.4X4A — Toxic effect of ketones, undetermined, initial encounter
- T52.4X4D — Toxic effect of ketones, undetermined, subsequent encounter
- T52.4X4S — Toxic effect of ketones, undetermined, sequela
- T52.8 — Toxic effects of other organic solvents
- T52.811 — Toxic effect of alkenes, accidental (unintentional)
- T52.811A — Toxic effect of alkenes, accidental (unintentional), initial encounter
- T52.811D — Toxic effect of alkenes, accidental (unintentional), subsequent encounter
- T52.811S — Toxic effect of alkenes, accidental (unintentional), sequela
- T52.812 — Toxic effect of alkenes, intentional self-harm