ICD-10-CM › S00-T88 › T36-T50 › T45.AX Poisoning by, adverse effect of... › T45.AX4
Poisoning by immune checkpoint inhibitors and immunostimulant drugs, undetermined
Not billableICD-10-CM diagnosis code.
This code exists but cannot be submitted on its own. It groups the more specific codes beneath it.
Submit one of these 3 more specific codes instead:
- T45.AX4A Poisoning by immune checkpoint inhibitors and immunostimulant drugs, undetermined, initial encounter
- T45.AX4D Poisoning by immune checkpoint inhibitors and immunostimulant drugs, undetermined, subsequent encounter
- T45.AX4S Poisoning by immune checkpoint inhibitors and immunostimulant drugs, undetermined, sequela
This code requires a seventh character. See the rule below.
What has happened to this code
Every change the publisher made, from 2025 to now.
- FY2025 Added to the code set Poisoning by immune checkpoint inhibitors and immunostimulant drugs, undetermined
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.
Inherited from T45 Poisoning by, adverse effect of and underdosing of primarily systemic and hematological agents, not elsewhere classified
Seventh character required
- The appropriate 7th character is to be added to each code from category T45
Inherited from the T36-T50 section Poisoning by, adverse effects of and underdosing of drugs, medicaments and biological substances (T36-T50)
Excludes1 - never coded here
- toxic reaction to local anesthesia in pregnancy (O29.3-)
Excludes2 - not included here
- abuse and dependence of psychoactive substances (F10-F19)
- abuse of non-dependence-producing substances (F55.-)
- immunodeficiency due to drugs (D84.821)
- drug reaction and poisoning affecting newborn (P00-P96)
- pathological drug intoxication (inebriation) (F10-F19)
Use additional code
- code(s) to specify:
- manifestations of poisoning
- underdosing or failure in dosage during medical and surgical care (Y63.6, Y63.8-Y63.9)
- underdosing of medication regimen (Z91.12-, Z91.13-)
Code first
- , for adverse effects, the nature of the adverse effect, such as:
- adverse effect NOS (T88.7)
- aspirin gastritis (K29.-)
- blood disorders (D56-D76)
- contact dermatitis (L23-L25)
- dermatitis due to substances taken internally (L27.-)
- nephropathy (N14.0-N14.2)
Includes
- adverse effect of correct substance properly administered
- poisoning by overdose of substance
- poisoning by wrong substance given or taken in error
- underdosing by (inadvertently) (deliberately) taking less substance than prescribed or instructed
Note
- The drug giving rise to the adverse effect should be identified by use of codes from categories T36-T50 with fifth or sixth character 5.
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.
- Immunostimulant drug
- Immune > checkpoint inhibitors
Codes in the same group
| Code | Description | Status |
|---|---|---|
| T45.AX1 | Poisoning by immune checkpoint inhibitors and immunostimulant drugs, accidental (unintentional) | Not billable |
| T45.AX2 | Poisoning by immune checkpoint inhibitors and immunostimulant drugs, intentional self-harm | Not billable |
| T45.AX3 | Poisoning by immune checkpoint inhibitors and immunostimulant drugs, assault | Not billable |
| T45.AX5 | Adverse effect of immune checkpoint inhibitors and immunostimulant drugs | Not billable |
| T45.AX6 | Underdosing of immune checkpoint inhibitors and immunostimulant drugs | Not billable |