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ICD-10-CM 2027 diagnosis code

T40.0X4Poisoning by opium, undetermined

Not billable — use a more specific codeRequires 7th character

T40.0X4 is a header code, so it can't be reported by itself. Choose one of the 3 more specific codes beneath it and add the required 7th character.

Code unchanged since ICD-10-CM took effect on October 1, 2015. Source: official FY2027 ICD-10-CM release from CDC/NCHS and CMS. Page updated September 29, 2026. About our data

About T40.0X4

T40.0X4 is the ICD-10-CM diagnosis code for poisoning by opium, undetermined. It belongs to category T40 (poisoning by, adverse effect of and underdosing of narcotics and psychodysleptics [hallucinogens]), block T36-T50 (poisoning by, adverse effects of and underdosing of drugs, medicaments and biological substances) and chapter 19 (injury, poisoning and certain other consequences of external causes). It is a header code, so it can't be reported by itself; one of its 3 subcodes must be used instead.

Within T40.0X (poisoning by, adverse effect of and underdosing of opium), T40.0X4 is specifically for poisoning by opium, undetermined. Related codes cover poisoning by opium, accidental (unintentional) (T40.0X1), poisoning by opium, intentional self-harm (T40.0X2), poisoning by opium, assault (T40.0X3), adverse effect of opium (T40.0X5) and underdosing of opium (T40.0X6).

Codes in this range require a 7th character: A for initial encounter, D for subsequent encounter and S for sequela. Use placeholder "X" characters to fill any empty positions before the 7th character.

It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.

7th character

The appropriate 7th character is to be added to each code from category T40

Notes that apply from higher levels

Instructions written at a parent level also apply to T40.0X4.

› From T40 Poisoning by, adverse effect of and underdosing of narcotics and psychodysleptics [hallucinogens]
Excludes2
  • drug dependence and related mental and behavioral disorders due to psychoactive substance use (F10.-F19.-)

Broader instructions also apply from T36-T50 Poisoning by, adverse effects of and underdosing of drugs, medicaments and biological substances and Chapter 19: Injury, poisoning and certain other consequences of external causes.

Table of Drugs & Neoplasms entries

Code history

  1. 2016
  2. 2017
  3. 2018
  4. 2019
  5. 2020
  6. 2021
  7. 2022
  8. 2023
  9. 2024
  10. 2025
  11. 2026
  12. 2027
  • FY2016 (effective 10/1/2015): Added (first year of ICD-10-CM)
  • No changes since FY2016.

Common questions about T40.0X4

Is T40.0X4 billable?

No. T40.0X4 is a header code. Report one of its more specific subcodes instead.