T40 Poisoning by, adverse effect of and underdosing of narcotics and psychodysleptics [hallucinogens]

⚠ Non-Billable ICD-10-CM 2026
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The ICD-10-CM code for Poisoning by, adverse effect of and underdosing of narcotics and psychodysleptics [hallucinogens] is T40 (FY2026). It is a non-billable category code — select a more specific code below for claims.

Classification

Section
T36-T50: Poisoning by, adverse effects of and underdosing of drugs, medicaments and biological substances (T36-T50)
Category T40
112 codes (86 billable)
FY2026 Status
Stable since FY2024
Excludes2
Not included here. These conditions are coded elsewhere but may be coded together if applicable.
  • drug dependence and related mental and behavioral disorders due to psychoactive substance use (F10.-F19.-)

Official Coding Guidelines

Sequence blood vessel/nerve injury first (fragment)

injury is to the blood vessels or nerves, that injury should be sequenced first.

— ICD-10-CM Official Guidelines for Coding and Reporting, FY2026, Section I.C.19.b.2
Do not assign injury codes for iatrogenic injuries; code complication

3) Iatrogenic injuries Injury codes from Chapter 19 should not be assigned for injuries that occur during, or as a result of, a medical intervention. Assign the appropriate complication code(s).

— ICD-10-CM Official Guidelines for Coding and Reporting, FY2026, Section I.C.19.b.3

Source: CMS — ICD-10-CM Official Guidelines for Coding and Reporting, FY2026

References

Cite This Page

Reference T40 with the canonical source and edition:

T40 — Poisoning by, adverse effect of and underdosing of narcotics and psychodysleptics [hallucinogens]. ICD-10 Coding Pro (ICD-10-CM FY2026). https://icd10codingpro.com/codes/T40

Canonical URL: https://icd10codingpro.com/codes/T40

Related Codes

All Codes in T40

Every most-specific code under T40 Poisoning by, adverse effect of and underdosing of narcotics and psychodysleptics [hallucinogens] (86 codes):

Show the complete T40 code list
T40.0X1 Poisoning by opium, accidental (unintentional) T40.0X2 Poisoning by opium, intentional self-harm T40.0X3 Poisoning by opium, assault T40.0X4 Poisoning by opium, undetermined T40.0X5 Adverse effect of opium T40.0X6 Underdosing of opium T40.1X1 Poisoning by heroin, accidental (unintentional) T40.1X2 Poisoning by heroin, intentional self-harm T40.1X3 Poisoning by heroin, assault T40.1X4 Poisoning by heroin, undetermined T40.2X1 Poisoning by other opioids, accidental (unintentional) T40.2X2 Poisoning by other opioids, intentional self-harm T40.2X3 Poisoning by other opioids, assault T40.2X4 Poisoning by other opioids, undetermined T40.2X5 Adverse effect of other opioids T40.2X6 Underdosing of other opioids T40.3X1 Poisoning by methadone, accidental (unintentional) T40.3X2 Poisoning by methadone, intentional self-harm T40.3X3 Poisoning by methadone, assault T40.3X4 Poisoning by methadone, undetermined T40.3X5 Adverse effect of methadone T40.3X6 Underdosing of methadone T40.411 Poisoning by fentanyl or fentanyl analogs, accidental (unintentional) T40.412 Poisoning by fentanyl or fentanyl analogs, intentional self-harm T40.413 Poisoning by fentanyl or fentanyl analogs, assault T40.414 Poisoning by fentanyl or fentanyl analogs, undetermined T40.415 Adverse effect of fentanyl or fentanyl analogs T40.416 Underdosing of fentanyl or fentanyl analogs T40.421 Poisoning by tramadol, accidental (unintentional) T40.422 Poisoning by tramadol, intentional self-harm T40.423 Poisoning by tramadol, assault T40.424 Poisoning by tramadol, undetermined T40.425 Adverse effect of tramadol T40.426 Underdosing of tramadol T40.491 Poisoning by other synthetic narcotics, accidental (unintentional) T40.492 Poisoning by other synthetic narcotics, intentional self-harm T40.493 Poisoning by other synthetic narcotics, assault T40.494 Poisoning by other synthetic narcotics, undetermined T40.495 Adverse effect of other synthetic narcotics T40.496 Underdosing of other synthetic narcotics T40.5X1 Poisoning by cocaine, accidental (unintentional) T40.5X2 Poisoning by cocaine, intentional self-harm T40.5X3 Poisoning by cocaine, assault T40.5X4 Poisoning by cocaine, undetermined T40.5X5 Adverse effect of cocaine T40.5X6 Underdosing of cocaine T40.601 Poisoning by unspecified narcotics, accidental (unintentional) T40.602 Poisoning by unspecified narcotics, intentional self-harm T40.603 Poisoning by unspecified narcotics, assault T40.604 Poisoning by unspecified narcotics, undetermined T40.605 Adverse effect of unspecified narcotics T40.606 Underdosing of unspecified narcotics T40.691 Poisoning by other narcotics, accidental (unintentional) T40.692 Poisoning by other narcotics, intentional self-harm T40.693 Poisoning by other narcotics, assault T40.694 Poisoning by other narcotics, undetermined T40.695 Adverse effect of other narcotics T40.696 Underdosing of other narcotics T40.711 Poisoning by cannabis, accidental (unintentional) T40.712 Poisoning by cannabis, intentional self-harm T40.713 Poisoning by cannabis, assault T40.714 Poisoning by cannabis, undetermined T40.715 Adverse effect of cannabis T40.716 Underdosing of cannabis T40.721 Poisoning by synthetic cannabinoids, accidental (unintentional) T40.722 Poisoning by synthetic cannabinoids, intentional self-harm T40.723 Poisoning by synthetic cannabinoids, assault T40.724 Poisoning by synthetic cannabinoids, undetermined T40.725 Adverse effect of synthetic cannabinoids T40.726 Underdosing of synthetic cannabinoids T40.8X1 Poisoning by lysergide [LSD], accidental (unintentional) T40.8X2 Poisoning by lysergide [LSD], intentional self-harm T40.8X3 Poisoning by lysergide [LSD], assault T40.8X4 Poisoning by lysergide [LSD], undetermined T40.901 Poisoning by unspecified psychodysleptics [hallucinogens], accidental (unintentional) T40.902 Poisoning by unspecified psychodysleptics [hallucinogens], intentional self-harm T40.903 Poisoning by unspecified psychodysleptics [hallucinogens], assault T40.904 Poisoning by unspecified psychodysleptics [hallucinogens], undetermined T40.905 Adverse effect of unspecified psychodysleptics [hallucinogens] T40.906 Underdosing of unspecified psychodysleptics [hallucinogens] T40.991 Poisoning by other psychodysleptics [hallucinogens], accidental (unintentional) T40.992 Poisoning by other psychodysleptics [hallucinogens], intentional self-harm T40.993 Poisoning by other psychodysleptics [hallucinogens], assault T40.994 Poisoning by other psychodysleptics [hallucinogens], undetermined T40.995 Adverse effect of other psychodysleptics [hallucinogens] T40.996 Underdosing of other psychodysleptics [hallucinogens]
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Reviewed by Prajwal Shrestha, CPC, CRC
Certified Professional Coder (CPC) and Certified Risk Adjustment Coder (CRC) · AAPC Member ID 01997614 · About · Editorial policy · Content last reviewed: 2025-10-01

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