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ICD-10-CM Current in FY 2027

T66.XXXA

Radiation sickness, unspecified, initial encounter

Release
FY 2027
Effective

Hierarchy

Where T66.XXXA sits in the official hierarchy. Each level is the code it is classified under.

  1. T66 Parent Radiation sickness, unspecified
  2. T66.XXXA This code Radiation sickness, unspecified, initial encounter

Official Coding Notes

Reproduced verbatim from the FY 2027 ICD-10-CM files. Notes labelled as inherited are declared on a parent code and apply here too.

Excludes1

specified adverse effects of radiation, such as:

Inherited from T66 — Radiation sickness, unspecified

Excludes1

burns (T20-T31)

Inherited from T66 — Radiation sickness, unspecified

Excludes1

leukemia (C91-C95)

Inherited from T66 — Radiation sickness, unspecified

Excludes1

radiation gastroenteritis and colitis ( K52.0 )

Inherited from T66 — Radiation sickness, unspecified

Excludes1

radiation pneumonitis ( J70.0 )

Inherited from T66 — Radiation sickness, unspecified

Excludes1

radiation related disorders of the skin and subcutaneous tissue (L55-L59)

Inherited from T66 — Radiation sickness, unspecified

Excludes1

sunburn ( L55 .-)

Inherited from T66 — Radiation sickness, unspecified

7th Character

The appropriate 7th character is to be added to code T66

Inherited from T66 — Radiation sickness, unspecified

7th Character

A - initial encounter

Inherited from T66 — Radiation sickness, unspecified

7th Character

D - subsequent encounter

Inherited from T66 — Radiation sickness, unspecified

7th Character

S - sequela

Inherited from T66 — Radiation sickness, unspecified

Version History

How T66.XXXA appears in each release imported from the official files, newest first.

  1. FY 2027 Effective

    Current

    Radiation sickness, unspecified, initial encounter

  2. FY 2026 Effective

    Unchanged

    Radiation sickness, unspecified, initial encounter

Other codes under T66

Data Source

Code information on this page is derived from the FY 2027 ICD-10-CM files published by CDC NCHS and CMS.

Release
FY 2027
Effective
Source file
icd10cm-code-descriptions-2027.zip

Official ICD-10-CM source files (opens in a new tab)

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