Skip to main content

T65.854 ICD-10-CM Code: Toxic effect of medetomidine, undetermined

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

No additional overview provided for this record.

Official Tabular Instructional Notes

Sequencing, inclusion, and exclusion notes published for T65.854 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).

Use Additional Code

Supplementary codes the tabular list directs you to add.

  • Use additional code to identify associated manifestations, such as:
  • bradycardia NOS (R00.1)
  • somnolence, stupor and coma (R40.-)
  • Use additional code(s):
  • for all associated manifestations of toxic effect, such as: respiratory conditions due to external agents (J60-J70)
  • personal history of foreign body fully removed (Z87.821)
  • to identify any retained foreign body, if applicable (Z18.-)

Associated Substances (1)

Substances from the official ICD-10-CM Table of Drugs and Chemicals that map to this code.

  • Medetomidine

Frequently Compared Codes

The official Excludes notes on T65.854 name these codes. Each comparison page covers when the two can — or must not — be reported together.

Change history

  • FY2027 — 2026-10-01
    Added to the code set
    Toxic effect of medetomidine, undetermined
    FY2027 changes

Verify Before Coding

  • Not billable as written — a more specific code is required.
  • Requires a 7th character. "The appropriate 7th character is to be added to each code from category T65" Options: T65.854A, T65.854D, T65.854S

From the code registry, the Medicare Code Editor, and the MS-DRG Definitions Manual. Check it against a full claim.

Relationships & Classification

Other codes that name T65.854 or its code family, from the CMS Table of Drugs and Chemicals.

3 Same-substance codes: T65.851Compare T65.854 vs T65.851 →, T65.852Compare T65.854 vs T65.852 →, T65.853Compare T65.854 vs T65.853 →.

Contextual Map

Every relationship of T65.854 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]
  • T51-T65 — Toxic effects of substances chiefly nonmedicinal as to source [Hierarchy]

Same substance

  • T65.851 — Toxic effect of medetomidine, accidental (unintentional) [Same substance]: “Same substance — accidental poisoning (Medetomidine)”
  • T65.852 — Toxic effect of medetomidine, intentional self-harm [Same substance]: “Same substance — intentional self-harm (Medetomidine)”
  • T65.853 — Toxic effect of medetomidine, assault [Same substance]: “Same substance — assault (Medetomidine)”

Referenced by Same-substance codes

  • T65.851 — Toxic effect of medetomidine, accidental (unintentional) [Same substance]: “Same substance — undetermined intent (Medetomidine)”
  • T65.852 — Toxic effect of medetomidine, intentional self-harm [Same substance]: “Same substance — undetermined intent (Medetomidine)”
  • T65.853 — Toxic effect of medetomidine, assault [Same substance]: “Same substance — undetermined intent (Medetomidine)”

Drugs & chemicals

  • Medetomidine — Medetomidine — Poisoning, Undetermined [Drug table]: “Medetomidine (Poisoning, Undetermined)”

Nearest codes (40)

  • T65 — Toxic effect of other and unspecified substances [Sibling]
  • T65.843A — Toxic effect of xylazine, assault, initial encounter [Sibling]
  • T65.843D — Toxic effect of xylazine, assault, subsequent encounter [Sibling]
  • T65.843S — Toxic effect of xylazine, assault, sequela [Sibling]
  • T65.844 — Toxic effect of xylazine, undetermined [Sibling]
  • T65.844A — Toxic effect of xylazine, undetermined, initial encounter [Sibling]
  • T65.844D — Toxic effect of xylazine, undetermined, subsequent encounter [Sibling]
  • T65.844S — Toxic effect of xylazine, undetermined, sequela [Sibling]
  • and 32 more

Change history

  • FY2027 — Added to the code set [Change history]

Frequently Asked Questions (FAQ) & Clinical Guidance

Can T65.854 be billed directly?

No. T65.854 (Toxic effect of medetomidine, undetermined) is a non-billable ICD-10-CM category code. A more specific billable subcode must be selected based on clinical documentation.

Does T65.854 require a 7th character?

Yes. The appropriate 7th character is to be added to each code from category T65.

Nearest Codes in This Family

Official ICD-10-CM classifications closest to T65.854 in its code family, with their registry titles.

  • T65.852S — Toxic effect of medetomidine, intentional self-harm, sequela
  • T65.853 — Toxic effect of medetomidine, assault
  • T65.853A — Toxic effect of medetomidine, assault, initial encounter
  • T65.853D — Toxic effect of medetomidine, assault, subsequent encounter
  • T65.853S — Toxic effect of medetomidine, assault, sequela
  • T65.854A — Toxic effect of medetomidine, undetermined, initial encounter
  • T65.854D — Toxic effect of medetomidine, undetermined, subsequent encounter
  • T65.854S — Toxic effect of medetomidine, undetermined, sequela
  • T65.89 — Toxic effect of other specified substances
  • T65.891 — Toxic effect of other specified substances, accidental (unintentional)

View all codes in the T65 family