T44.994 vs T44.996

T44.994 (Poisoning by other drug primarily affecting the autonomic nervous system, undetermined) compared with T44.996 (Underdosing of other drug primarily affecting the autonomic nervous system), from the official CMS tabular data. T44.994 and T44.996 code the same substance (Amezinium) with a different intent.

Relationship

Informational

Drug table relationship

T44.994

Poisoning by other drug primarily affecting the autonomic nervous system, undetermined

↔

T44.996

Underdosing of other drug primarily affecting the autonomic nervous system

Same substance, different circumstance of exposure.

Same substance — underdosing (Amezinium)

Accidental poisoning, intentional self-harm, assault, undetermined intent, adverse effect and underdosing are mutually exclusive columns — exactly one applies to a given encounter.

Source: CMS Table of Drugs and Chemicals

Can these codes be reported together?

Same substance, different intent. T44.994 and T44.996 code the same substance (Amezinium) with a different circumstance of exposure.

From the CMS Table of Drugs and Chemicals: accidental poisoning, intentional self-harm, assault, undetermined intent, adverse effect and underdosing are mutually exclusive columns — only one of them applies to a given encounter.

Side by side

	T44.994Poisoning by other drug primarily affecting the autonomic nervous system, undetermined	T44.996Underdosing of other drug primarily affecting the autonomic nervous system
Billing status	Non-billable header Report instead: T44.994A, T44.994D, T44.994S	Non-billable header Report instead: T44.996A, T44.996D, T44.996S
Classification	S00-T88 — Injury, Poisoning and Certain Other Consequences of External Causes (S00-T88)	S00-T88 — Injury, Poisoning and Certain Other Consequences of External Causes (S00-T88)
Definition	Poisoning by other drug primarily affecting the autonomic nervous system, undetermined is a non-billable ICD-10-CM category code (T44.994).	Underdosing of other drug primarily affecting the autonomic nervous system is a non-billable ICD-10-CM category code (T44.996).
7th character	The appropriate 7th character is to be added to each code from category T44	The appropriate 7th character is to be added to each code from category T44
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	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
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)	code(s) to specify: manifestations of poisoning underdosing or failure in dosage during medical and surgical care (Y63.6, Y63.8-Y63.9)
Code first	, for adverse effects, the nature of the adverse effect, such as: adverse effect NOS (T88.7)	, for adverse effects, the nature of the adverse effect, such as: adverse effect NOS (T88.7)

Edit this comparison Check a whole claim

Derived from the official CMS ICD-10-CM tabular data (FY2026). Not billing advice; verify sequencing rules for the encounter. All data sources