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Compare/T42.6 vs T43

T42.6 vs T43

T42.6 (Poisoning by, adverse effect of and underdosing of other antiepileptic and sedative-hypnotic drugs) compared with T43 (Poisoning by, adverse effect of and underdosing of psychotropic drugs, not elsewhere classified), from the official CMS tabular data. Both may be reported when both conditions are documented (Excludes2).

Can these codes be reported together?

Yes, when both are documented. T43 carries an Excludes2 note covering T42.6: “methaqualone (T42.6-)”

Excludes2 marks distinct conditions — both may be reported when both are documented.

Side by side

T42.6Poisoning by, adverse effect of and underdosing of other antiepileptic and sedative-hypnotic drugsT43Poisoning by, adverse effect of and underdosing of psychotropic drugs, not elsewhere classified
Billing statusNon-billable header

Report instead: T42.6X1A, T42.6X1D, T42.6X1S, T42.6X2A, T42.6X2D

Non-billable header

Report instead: T43.011A, T43.011D, T43.011S, T43.012A, T43.012D

ClassificationS00-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)
DefinitionPoisoning by, adverse effect of and underdosing of other antiepileptic and sedative-hypnotic drugs is a non-billable ICD-10-CM category code (T42.6).Poisoning by, adverse effect of and underdosing of psychotropic drugs, not elsewhere classified is a non-billable ICD-10-CM category code (T43).
7th characterThe appropriate 7th character is to be added to each code from category T42The appropriate 7th character is to be added to each code from category T43
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)

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