ICD-10-CM › S00-T88 › T66-T78 › T codes › T66

T66

Radiation sickness, unspecified

Not billableICD-10-CM diagnosis code.

This code exists but cannot be submitted on its own. It groups the more specific codes beneath it.

A category header for its whole life, FY2016 onwards. It has never been valid for submission on its own.

Submit one of these 3 more specific codes instead:

  • T66.XXXA Radiation sickness, unspecified, initial encounter
  • T66.XXXD Radiation sickness, unspecified, subsequent encounter
  • T66.XXXS Radiation sickness, unspecified, sequela

This code requires a seventh character. See the rule below.

What has happened to this code

Every change the publisher made, from 2014 to now. Entries marked draft are from the pre-implementation releases: ICD-10 took effect on 1 October 2015, so nothing before FY2016 was ever valid on a claim.

  1. FY2014 Added to the draft code set draft Radiation sickness, unspecified

Official coding rules

Published by CDC for FY2027. A rule attached to a category binds every code beneath it, so the rules inherited from this code's ancestors are shown with the code they come from.

This code

Seventh character required

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

Excludes1 - never coded here

  • specified adverse effects of radiation, such as:
  • burns (T20-T31)
  • leukemia (C91-C95)
  • radiation gastroenteritis and colitis (K52.0)
  • radiation pneumonitis (J70.0)
  • radiation related disorders of the skin and subcutaneous tissue (L55-L59)
  • sunburn (L55.-)

Inherited from the T66-T78 section Other and unspecified effects of external causes (T66-T78)

Code also

  • , if applicable, place of occurrence, such as:
  • highway rest stop (Y92.523)
  • school (private) (public) (state) as the place of occurrence of the external cause (Y92.21-)
  • service areas as the place of occurrence of the external cause (Y92.52-)
  • single-family non-institutional (private) house as the place of occurrence of the external cause (Y92.01-)
  • transport vehicle as the place of occurrence of the external cause (Y92.81-)

How CDC's index refers to this code

Wording from the official alphabetic index. Much of it appears nowhere in the code description, which is why a search for the everyday phrase so often finds nothing.