Is ICD-10-CM code T52.823A billable?

Yes, T52.823A (Toxic effect of cycloparaffins, assault, initial encounter) is a billable ICD-10-CM diagnosis code, valid for reimbursement on HIPAA-covered transactions for FY2027.

What chapter does ICD-10-CM code T52.823A belong to?

T52.823A belongs to Chapter 19 of the ICD-10-CM tabular list: S00–T88 (Injury, Poisoning and Certain Other Consequences of External Causes).

Is T52.823A a new ICD-10-CM code for 2027?

Yes, T52.823A was added or revised in the FY2027 ICD-10-CM update, effective October 1, 2026, as published by the Centers for Medicare and Medicaid Services (CMS).

T52.823ABillable, valid for claims from October 1, 2026New for FY2027

Toxic effect of cycloparaffins, assault, initial encounter

Under T52.823 Toxic effect of cycloparaffins, assault, in Toxic effects of substances chiefly nonmedicinal as to source (T51-T65), chapter 19: Injury, Poisoning and Certain Other Consequences of External Causes

T52.823A is billable and valid on claims for FY 2027. If the record has more detail, check the other codes under T52.823 below.
As a secondary diagnosis it is not a CC or MCC, so it doesn't raise the MS-DRG payment.

Instructional notes

Also applies, from T52.82: Toxic effects of cycloparaffins

These notes sit on T52.82 and apply to every code under it, including T52.823A.

Includes: conditions that are coded here

Toxic effects of naphthenes
Toxic effects of cycloalkanes

Also applies, from T52: Toxic effect of organic solvents

These notes sit on T52 and apply to every code under it, including T52.823A.

Excludes1: not coded here, use a different code

halogen derivatives of aliphatic and aromatic hydrocarbons (T53.-)

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 T52.823A.

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.-)

Other codes under T52.823

Toxic effect of cycloparaffins, assault

T52.823AToxic effect of cycloparaffins, assault, initial encounter(this code)
T52.823DToxic effect of cycloparaffins, assault, subsequent encounter
T52.823SToxic effect of cycloparaffins, assault, sequela

MS-DRGs

As the principal diagnosis, this code groups 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.

Code history

Added in FY2027 (effective October 1, 2026). Before that, these cases were coded as T52.8X3A. No changes since.