ICD-10-CM 2027 diagnosis code
T40Poisoning by, adverse effect of and underdosing of narcotics and psychodysleptics [hallucinogens]
T40 is a header code, so it can't be reported by itself. Choose one of the 10 more specific codes beneath it.Short description: Narcotics and psychodysleptics
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
T40 is the ICD-10-CM diagnosis code for poisoning by, adverse effect of and underdosing of narcotics and psychodysleptics [hallucinogens]. It belongs to 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 10 subcodes must be used instead.
To report this condition, pick the subcode that matches the documentation: T40.0 (opium), T40.1 (heroin), T40.2 (opioids), T40.3 (methadone), T40.4 (narcotics), T40.5 (cocaine), T40.6 (narcotics), T40.7 ((derivatives)) and 2 more.
The conditions in its Excludes2 note aren't part of T40, but may be coded alongside it if the patient has both: drug dependence and related mental and behavioral disorders due to psychoactive substance use (F10.-F19.-).
It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.
Specific codes under T40
- T40.0Poisoning by, adverse effect of and underdosing of opium
- T40.1Poisoning by and adverse effect of heroin
- T40.2Poisoning by, adverse effect of and underdosing of other opioids
- T40.3Poisoning by, adverse effect of and underdosing of methadone
- T40.4Poisoning by, adverse effect of and underdosing of other synthetic narcotics
- T40.41Poisoning by, adverse effect of and underdosing of fentanyl or fentanyl analogs
- T40.411Poisoning by fentanyl or fentanyl analogs, accidental (unintentional)
- T40.412Poisoning by fentanyl or fentanyl analogs, intentional self-harm
- T40.413Poisoning by fentanyl or fentanyl analogs, assault
- T40.414Poisoning by fentanyl or fentanyl analogs, undetermined
- T40.415Adverse effect of fentanyl or fentanyl analogs
- T40.416Underdosing of fentanyl or fentanyl analogs
- T40.42Poisoning by, adverse effect of and underdosing of tramadol
- T40.49Poisoning by, adverse effect of and underdosing of other synthetic narcotics
- T40.491Poisoning by other synthetic narcotics, accidental (unintentional)
- T40.492Poisoning by other synthetic narcotics, intentional self-harm
- T40.493Poisoning by other synthetic narcotics, assault
- T40.494Poisoning by other synthetic narcotics, undetermined
- T40.495Adverse effect of other synthetic narcotics
- T40.496Underdosing of other synthetic narcotics
- T40.41Poisoning by, adverse effect of and underdosing of fentanyl or fentanyl analogs
- T40.5Poisoning by, adverse effect of and underdosing of cocaine
- T40.6Poisoning by, adverse effect of and underdosing of other and unspecified narcotics
- T40.60Poisoning by, adverse effect of and underdosing of unspecified narcotics
- T40.601Poisoning by unspecified narcotics, accidental (unintentional)
- T40.602Poisoning by unspecified narcotics, intentional self-harm
- T40.603Poisoning by unspecified narcotics, assault
- T40.604Poisoning by unspecified narcotics, undetermined
- T40.605Adverse effect of unspecified narcotics
- T40.606Underdosing of unspecified narcotics
- T40.69Poisoning by, adverse effect of and underdosing of other narcotics
- T40.60Poisoning by, adverse effect of and underdosing of unspecified narcotics
- T40.7Poisoning by, adverse effect of and underdosing of cannabis (derivatives)
- T40.71Poisoning by, adverse effect of and underdosing of cannabis (derivatives)
- T40.72Poisoning by, adverse effect of and underdosing of synthetic cannabinoids
- T40.721Poisoning by synthetic cannabinoids, accidental (unintentional)
- T40.722Poisoning by synthetic cannabinoids, intentional self-harm
- T40.723Poisoning by synthetic cannabinoids, assault
- T40.724Poisoning by synthetic cannabinoids, undetermined
- T40.725Adverse effect of synthetic cannabinoids
- T40.726Underdosing of synthetic cannabinoids
- T40.8Poisoning by and adverse effect of lysergide [LSD]
- T40.9Poisoning by, adverse effect of and underdosing of other and unspecified psychodysleptics [hallucinogens]
- T40.90Poisoning by, adverse effect of and underdosing of unspecified psychodysleptics [hallucinogens]
- T40.901Poisoning by unspecified psychodysleptics [hallucinogens], accidental (unintentional)
- T40.902Poisoning by unspecified psychodysleptics [hallucinogens], intentional self-harm
- T40.903Poisoning by unspecified psychodysleptics [hallucinogens], assault
- T40.904Poisoning by unspecified psychodysleptics [hallucinogens], undetermined
- T40.905Adverse effect of unspecified psychodysleptics [hallucinogens]
- T40.906Underdosing of unspecified psychodysleptics [hallucinogens]
- T40.99Poisoning by, adverse effect of and underdosing of other psychodysleptics [hallucinogens]
- T40.991Poisoning by other psychodysleptics [hallucinogens], accidental (unintentional)
- T40.992Poisoning by other psychodysleptics [hallucinogens], intentional self-harm
- T40.993Poisoning by other psychodysleptics [hallucinogens], assault
- T40.994Poisoning by other psychodysleptics [hallucinogens], undetermined
- T40.995Adverse effect of other psychodysleptics [hallucinogens]
- T40.996Underdosing of other psychodysleptics [hallucinogens]
- T40.90Poisoning by, adverse effect of and underdosing of unspecified psychodysleptics [hallucinogens]
Coding notes
Notes that apply from higher levels
Instructions written at a parent level also apply to T40.
Code history
- 2016
- 2017
- 2018
- 2019
- 2020
- 2021
- 2022
- 2023
- 2024
- 2025
- 2026
- 2027
- FY2016 (effective 10/1/2015): Added (first year of ICD-10-CM)
- No changes since FY2016.
Common questions about T40
Is T40 billable?
- No. T40 is a header code. Report one of its more specific subcodes instead.