Is ICD-10-CM code T65.851 billable?

No, T65.851 (Toxic effect of medetomidine, accidental (unintentional)) is a non-billable ICD-10-CM code. It must be coded to a more specific subcategory before it can be used for reimbursement.

What chapter does ICD-10-CM code T65.851 belong to?

T65.851 belongs to Chapter 19 of the ICD-10-CM tabular list: S00–T88 (Injury, Poisoning and Certain Other Consequences of External Causes).

T65.851Not billable, use a more specific code below

Toxic effect of medetomidine, accidental (unintentional)

Under T65.85 Toxic effect of medetomidine, in Toxic effects of substances chiefly nonmedicinal as to source (T51-T65), chapter 19: Injury, Poisoning and Certain Other Consequences of External Causes

3 billable codes under T65.851: none are a CC or MCC; none map to an HCC.

Instructional notes

Includes: conditions that are coded here

Toxic effect of medetomidine NOS

Also applies, from T65.85: Toxic effect of medetomidine

These notes sit on T65.85 and apply to every code under it, including T65.851.

Use additional code: add a second code for this, listed after this one

code to identify associated manifestations, such as:
bradycardia NOS (R00.1)
somnolence, stupor and coma (R40.-)

Also applies, from Toxic effects of substances chiefly nonmedicinal as to source (T51-T65)

These notes sit on T51-T65 and apply to every code under it, including T65.851.

Excludes1: not coded here, use a different code

contact with and (suspected) exposure to toxic substances (Z77.-)

Use additional code: add a second code for this, listed after this one

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.-)

All codes under T65.851

T65.851 can't be used on a claim. Pick a billable code below; grey headings group them.

MS-DRGs

As the principal diagnosis, the billable codes under T65.851 group to these MS-DRGs (v44.0). Which one applies depends on procedures performed, secondary diagnoses (CC/MCC), and the patient's age and discharge status.

DRG 917 Poisoning and Toxic Effects of Drugs with MCC (1 of 3 codes)
DRG 918 Poisoning and Toxic Effects of Drugs without MCC (1 of 3 codes)
DRG 922 Other Injury, Poisoning and Toxic Effect Diagnoses with MCC (1 of 3 codes)
DRG 923 Other Injury, Poisoning and Toxic Effect Diagnoses without MCC (1 of 3 codes)
DRG 949 Aftercare with CC/MCC (1 of 3 codes)
DRG 950 Aftercare without CC/MCC (1 of 3 codes)

About the condition

Plain-language background from MedlinePlus (National Library of Medicine), not coding guidance.

Poisoning

A poison is any substance that is harmful to your body. You might swallow it, inhale it, inject it, or absorb it through your skin. Any substance can be poisonous if too much is taken. Poisons can include:

Code history

Added in FY2027 (effective October 1, 2026). No changes since.