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T58.12XA

T58.12XA: Toxic effect of carbon monoxide from utility gas, intentional self-harm, initial encounter

Billable / specific codeICD-10-CM

T58.12XA is a billable, specific ICD-10-CM code for toxic effect of carbon monoxide from utility gas, intentional self-harm, initial encounter. It is valid for submission on a claim.

Check T58.12XA with the rest of the claim: free scrubber

7th character "A": initial encounter

The appropriate 7th character is to be added to each code from category T58

A
initial encounter
D
subsequent encounter
S
sequela

Other codes that can never be billed with T58.12XA

Their own Excludes1 notes name this code, so the conflict is not listed above.

  • R09.0Asphyxia and hypoxemia
  • T71Asphyxiation

Risk adjustment

T58.12XA risk-adjusts. Under the CMS-HCC V28 model it maps to these categories:

  • HCC 155 Major Depression, Moderate or Severe, without Psychosis0.299 RAF
  • HCC 155 Major Depression, Moderate or Severe, without Psychosis0.299 RAF

Coefficient shown for the Community Non-dual Aged segment. A higher HCC in the same hierarchy will suppress this one, so capturing it does not always add score. Look up the whole chart to see which of its HCCs the hierarchy would zero.

Medicare coverage

T58.12XA is named in 5 Medicare coverage policies: 5 listing it as supporting medical necessity. Which one applies depends on your Medicare contractor.

  • A56612Billing and Coding: CT of the Head
  • A56625Billing and Coding: Echocardiography
  • A57205Billing and Coding: Oximetry Services
  • A57306Billing and Coding: Transthoracic Echocardiography (TTE)

Code history

Unchanged in every release from FY2024 to FY2027.

Other codes under T58.12

ICD-10-CMFY2027· effective October 1, 2026

Loaded directly from the CMS/NCHS ICD-10-CM public-domain release: see data sources and our editorial policy. If this page disagrees with the CMS tabular list, this page is wrong. Reference information for professional coders; not medical or billing advice.