2026 ICD-10-CM Diagnosis Code T65.843A

Toxic effect of xylazine, assault, initial encounter

ICD-10-CM Code:
T65.843A
ICD-10 Code for:
Toxic effect of xylazine, assault, initial encounter
Is Billable?
Yes - Valid for Submission
Code Navigator:

T65.843A is a billable diagnosis code used to specify a medical diagnosis of toxic effect of xylazine, assault, initial encounter. The code is valid during the current fiscal year for the submission of HIPAA-covered transactions from October 01, 2025 through September 30, 2026.

T65.843A is an initial encounter code, includes a 7th character and should be used while the patient is receiving active treatment for a condition like toxic effect of xylazine assault. According to ICD-10-CM Guidelines an "initial encounter" doesn't necessarily means "initial visit". The 7th character should be used when the patient is undergoing active treatment regardless if new or different providers saw the patient over the course of a treatment. The appropriate 7th character codes should also be used even if the patient delayed seeking treatment for a condition.

Code Classification

  • Injury, poisoning and certain other consequences of external causes
    S00–T88
    • Toxic effects of substances chiefly nonmedicinal as to source
      T51-T65
      • Toxic effect of other and unspecified substances
        T65

Clinical Information

  • Xylazine

    an adrenergic alpha-2 agonist used as a sedative, analgesic and centrally acting muscle relaxant in veterinary medicine.

Coding Guidelines

The appropriate 7th character is to be added to each code from block Toxic effect of other and unspecified substances (T65). Use the following options for the aplicable episode of care:

  • A - initial encounter
  • D - subsequent encounter
  • S - sequela

New 2026 ICD-10-CM Code

T65.843A is new to ICD-10-CM code set for the FY 2026, effective October 1, 2025. The National Center for Health Statistics (NCHS) has published an update to the ICD-10-CM diagnosis codes which became effective October 1, 2025. This is a new and revised code for the FY 2026 (October 1, 2025 - September 30, 2026).

Replacement Code

T65843A replaces the following previously assigned ICD-10-CM code(s):

  • T65.893A - Toxic effect of oth substances, assault, init encntr

Table of Drugs and Chemicals

The parent code T65.843 of the current diagnosis code is referenced in the Table of Drugs and Chemicals, this table contains a classification of drugs, industrial solvents, corrosive gases, noxious plants, pesticides, and other toxic agents.

According to ICD-10-CM coding guidelines it is advised to do not code directly from the Table of Drugs and Chemicals, instead always refer back to the Tabular List when doing the initial coding. Each substance in the table is assigned a code according to the poisoning classification and external causes of adverse effects. It is important to use as many codes as necessary to specify all reported drugs, medicinal or chemical substances. If the same diagnosis code describes the causative agent for more than one adverse reaction, poisoning, toxic effect or underdosing, utilize the code only once.

Substance Poisoning
Accidental
(unintentional)
Poisoning
Accidental
(self-harm)
Poisoning
Assault
Poisoning
Undetermined
Adverse
effect
Underdosing
XylazineT65.841T65.842T65.843T65.844  

Code History

  • FY 2026 - Code Added, effective from 10/1/2025 through 9/30/2026