2026 ICD-10-CM Diagnosis Code T73.2XXAExhaustion due to exposure, initial encounter

ICD-10-CM Codes›S00–T88›T66-T78›T73

ICD-10-CM T73.2XXA
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

T73.2XXA is a billable ICD-10-CM diagnosis code for exhaustion due to exposure, initial encounter. The 7th character A marks it as an initial encounter code, used while the patient is receiving active treatment. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 922 through 923. Coders also document this condition as exhaustion - physiological. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Effect of other external causes, initial encounter; External cause codes: intent of injury, accidental/unintentional; and External cause codes: natural/environment; initial encounter.

Code Identity

ICD-10-CM Code
T73.2XXA
Billable Status
Yes — Valid for Submission
Code Describes
Exhaustion due to exposure, initial encounter
Short Description
Exhaustion due to exposure, initial encounter
Same as the full description in the CMS dataset.
Parent Code
T73.2
Exhaustion due to exposure

Code Classification

ChapterS00–T88Injury, poisoning and certain other consequences of external causes
SectionT66-T78Other and unspecified effects of external causes
CategoryT73Effects of other deprivation
This CodeT73.2XXAExhaustion due to exposure, initial encounter

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Exhaustion - physiological
  • Exhaustion due to exposure

Coding GuidelinesGuidance

The appropriate 7th character is to be added to each code from block Effects of other deprivation (T73). Use the following options for the applicable episode of care:

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

Source: ICD-10-CM Official Guidelines for Coding and Reporting, FY 2026, published by CMS and the National Center for Health Statistics.

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR INJ021
Effect of other external causes, initial encounter
Default principal diagnosis: inpatient Yes · outpatient Yes
CCSR EXT020
External cause codes: intent of injury, accidental/unintentional
Default principal diagnosis: inpatient No · outpatient No
CCSR EXT011
External cause codes: natural/environment; initial encounter
Default principal diagnosis: inpatient No · outpatient No

Convert T73.2XXA to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
994.4 Exhaustion-exposure
ApproximateCombination The match is approximate, and more than one code can be needed to describe the source diagnosis. Confirm with contextual judgment.
ICD-9-CM
E904.3 Exposure NEC
ApproximateCombination The match is approximate, and more than one code can be needed to describe the source diagnosis. Confirm with contextual judgment.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About T73.2XXAOverview

Is T73.2XXA (Exhaustion due to exposure) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report exhaustion due to exposure, initial encounter on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What does the 7th character A in T73.2XXA mean?

The final character A marks the initial encounter: use it while the patient is receiving active treatment for exhaustion due to exposure, such as an emergency visit or first evaluation.

What MS-DRG does T73.2XXA group to?

When exhaustion due to exposure, initial encounter is the principal diagnosis on an inpatient stay, it groups to MS-DRG 922, 923, with relative weights from 1.0177 to 1.7494 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of T73.2XXA?

Under the General Equivalence Mappings, exhaustion due to exposure, initial encounter converts to ICD-9-CM 994.4 (exhaustion-exposure) and E904.3 (exposure NEC). The mapping is approximate, so confirm the match fits the documentation.

Footnotes

[1] Not chronic - A diagnosis code that does not fit the criteria for chronic condition (duration, ongoing medical treatment, and limitations) is considered not chronic. Some codes designated as not chronic are acute conditions. Other diagnosis codes that indicate a possible chronic condition, but for which the duration of the illness is not specified in the code description (i.e., we do not know the condition has lasted 12 months or longer) also are considered not chronic.