ICD10

ICD-10 Code T42.5: Poisoning by, adverse effect of and underdosing of mixed antiepileptics

T42.5 is an ICD-10 diagnosis entry used to group records related to Poisoning by, adverse effect of and underdosing of mixed antiepileptics. You may see this entry in coding references, medical records, or claims workflows when a broader diagnosis category is being reviewed before a more specific code is chosen. ICD-10 entries help standardize how diagnoses are organized for coding, reporting, analytics, and documentation. This code sits within the broader ICD-10 area for Injury, poisoning and certain other consequences of external causes (S00-T88).

Reviewed by HealthAssure Clinical TeamUpdated 21 May 2026

What is this code?

ICD-10 entries help standardize how diagnoses are organized for coding, reporting, analytics, and documentation. This code sits within the broader ICD-10 area for Injury, poisoning and certain other consequences of external causes (S00-T88).

When is it used?

  • May be used when a clinician documents poisoning by, adverse effect of and underdosing of mixed antiepileptics in a patient's medical record.
  • May appear in hospital records, claims, referrals, and clinical documentation.
  • This code may act more like a grouping or parent code, so a more specific child code may be used in final documentation when available.

What it does not mean

  • A code alone does not explain severity, treatment plan, or outcome.
  • A medical code should not be treated as a substitute for a doctor's diagnosis or advice.
  • This entry may represent a broader category rather than the most specific billable code.

Code hierarchy

chapter
19Injury, poisoning and certain other consequences of external causes (S00-T88)
block
T07-T88Injury, poisoning and certain other consequences of external causes
block
T36-T50Poisoning by, adverse effects of and underdosing of drugs, medicaments and biological substances
category
T42Poisoning by, adverse effect of and underdosing of antiepileptic, sedative- hypnotic and antiparkinsonism drugs
currentT42

Where you may see this code

You may see this entry in coding references, medical records, or claims workflows when a broader diagnosis category is being reviewed before a more specific code is chosen.

Related specialists

Emergency Medicine SpecialistOrthopedic SpecialistNeurologist

Coding guidelines

Compatibility

Legacy code aligns to an official FY 2026 category. Frontend should resolve to the official category page and surface the billable child codes.
Legacy codes
T42.5

Common synonyms

Poisoning by, adverse effect of and underdosing of mixed antiepileptics

Frequently asked questions

Code details

CodeT42.5
SystemICD10
Display namePoisoning by, adverse effect of and underdosing of mixed antiepileptics
ChapterInjury, poisoning and certain other consequences of external causes (S00-T88)
BlockPoisoning by, adverse effects of and underdosing of drugs, medicaments and biological substances

Flags

BillableNo
Valid clinical useNo

Source

SourceICD-10
Version2026-annual
Releaseannual
Year2026

About this content

This page is prepared by HealthAssure's clinical team using official coding standards from ICD-10. AI tools assist with drafting explanations, which are then reviewed and verified by healthcare professionals for accuracy. This content is for informational purposes and does not replace professional medical advice. Meet our team.