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T42.6X4D

T42.6X4D: Poisoning by other antiepileptic and sedative-hypnotic drugs, undetermined, subsequent encounter

Billable / specific codeICD-10-CMPOA exempt

T42.6X4D is a billable, specific ICD-10-CM code for poisoning by other antiepileptic and sedative-hypnotic drugs, undetermined, subsequent encounter. It is valid for submission on a claim.

Check T42.6X4D with the rest of the claim: free scrubber

7th character "D": subsequent encounter

The appropriate 7th character is to be added to each code from category T42

A
initial encounter
D
subsequent encounter
S
sequela

Excludes1 inherited from the categories above T42.6X4D

A category’s note binds every code beneath it.

Written on T42.6: Poisoning by, adverse effect of and underdosing of other antiepileptic and sedative-hypnotic drugs

  • poisoning by, adverse effect of and underdosing of carbamazepine (T42.1-)

Excludes2 inherited from the categories above T42.6X4D

Not part of this code, but both may be coded when both are present.

Written on T42: Poisoning by, adverse effect of and underdosing of antiepileptic, sedative- hypnotic and antiparkinsonism drugs

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

Risk adjustment

No CMS-HCC V28 category: this code does not change a RAF score.

Medicare coverage

T42.6X4D is named in 2 Medicare coverage policies: 2 listing it as supporting medical necessity. Which one applies depends on your Medicare contractor.

  • A56612Billing and Coding: CT of the Head
  • A56645Billing and Coding: Controlled Substance Monitoring and Drugs of Abuse Testing

Code history

Unchanged in every release from FY2024 to FY2027.

Other codes under T42.6X4

ICD-10-CMFY2027· effective October 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.