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T40

T40Poisoning by, adverse effect of and underdosing of narcotics and psychodysleptics [hallucinogens]

Non-billable headerICD-10-CM

T40 is a non-billable header ICD-10-CM code for poisoning by, adverse effect of and underdosing of narcotics and psychodysleptics [hallucinogens]. It cannot be billed on its own: choose one of the more specific child codes below. This code also requires a 7th character before it is complete.

This code requires a 7th character

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

A
initial encounter
D
subsequent encounter
S
sequela

Excludes2 — not included here, but may coexist

The excluded condition is not part of this code, but a patient can have both. You may code both.

  • drug dependence and related mental and behavioral disorders due to psychoactive substance use (F10.-F19.-)

Other codes that can never be billed with T40

These codes carry an Excludes1 note pointing at T40. The conflict binds both ways, but ICD-10-CM only writes it down on one side — so you would not find this by reading T40 alone.

  • T41Poisoning by, adverse effect of and underdosing of anesthetics and therapeutic gases
  • T43.6Poisoning by, adverse effect of and underdosing of psychostimulants

Risk adjustment

T40 does not map to an HCC and does not risk-adjust under CMS-HCC V28. That is normal — most ICD-10 codes do not. It still needs to be coded correctly; it just will not move a RAF score.

Code to one of these instead T40

10 child codes. Green means billable.

Questions about T40

Is T40 a billable ICD-10-CM code?
No. T40 is a non-billable header code. Code to a higher level of specificity using one of its child codes.
Where does T40 sit in the tabular list?
Injury, poisoning and certain other consequences of external causes (S00-T88), in the block Poisoning by, adverse effects of and underdosing of drugs, medicaments and biological substances (T36-T50).
ICD-10-CMFY2026-Apr· effective April 1, 2026

Loaded directly from the CMS/NCHS ICD-10-CM public-domain release — see data sources and our editorial policy. If this page disagrees with the CMS tabular list, this page is wrong. Reference information for professional coders; not medical or billing advice.