T42 ICD-10-CM Code: Poisoning by, adverse effect of and underdosing of antiepileptic, sedative- hypnotic and antiparkinsonism drugs
A clear reference for the official code description, hierarchy, and related coding information from the FY 2027 U.S. release.
Official description
T42Poisoning by, adverse effect of and underdosing of antiepileptic, sedative- hypnotic and antiparkinsonism drugs
ICD-10-CM diagnosis code · United States clinical modification
Where T42 sits
- 1
Chapter 19
Injury, poisoning and certain other consequences of external causes (S00-T88)
- 2
Section
Poisoning by, adverse effects of and underdosing of drugs, medicaments and biological substances (T36-T50)
- 3
Category T42
Poisoning by, adverse effect of and underdosing of antiepileptic, sedative- hypnotic and antiparkinsonism drugs
- 4
Code T42
Poisoning by, adverse effect of and underdosing of antiepileptic, sedative- hypnotic and antiparkinsonism drugs
Codes under T42
T42 is a non-billable category. Choose the child code that best matches the documented diagnosis.
T42.0Poisoning by, adverse effect of and underdosing of hydantoin derivativesT42.1Poisoning by, adverse effect of and underdosing of iminostilbenesT42.2Poisoning by, adverse effect of and underdosing of succinimides and oxazolidinedionesT42.3Poisoning by, adverse effect of and underdosing of barbituratesT42.4Poisoning by, adverse effect of and underdosing of benzodiazepinesT42.5Poisoning by, adverse effect of and underdosing of mixed antiepilepticsT42.6Poisoning by, adverse effect of and underdosing of other antiepileptic and sedative-hypnotic drugsT42.7Poisoning by, adverse effect of and underdosing of unspecified antiepileptic and sedative-hypnotic drugsT42.8Poisoning by, adverse effect of and underdosing of antiparkinsonism drugs and other central muscle-tone depressantsNotes for this code
Inclusion terms
No inclusion terms are listed for T42.
Code first
No “code first” instruction is listed for T42.
Use additional code
No “use additional code” instruction is listed for T42.
Excludes1
Conditions that should not be reported together with this code.
No Excludes1 note is listed for T42.
Excludes2
Conditions not included here that may be reported separately when present.
- drug dependence and related mental and behavioral disorders due to psychoactive substance use (F10.--F19.-)
Source and release
- Data release
- U.S. ICD-10-CM · FY 2027
- Effective date
- Oct 1, 2026
- Publisher
- Vero Scribe Inc.
This reference is generated from Vero’s ICD-10-CM description, hierarchy, and code-note dataset. The visible content and structured data share that source.
Frequently asked questions
What does ICD-10-CM code T42 mean?
T42 is the FY 2027 U.S. ICD-10-CM code for “Poisoning by, adverse effect of and underdosing of antiepileptic, sedative- hypnotic and antiparkinsonism drugs.”
Is T42 a billable or specific ICD-10-CM code?
No. T42 has more specific child codes in the FY 2027 reference data. Select the code that matches the documentation and confirm the active code set and payer requirements.
Where is T42 located in ICD-10-CM?
T42 is listed in Chapter 19, Injury, poisoning and certain other consequences of external causes (S00-T88), within Poisoning by, adverse effects of and underdosing of drugs, medicaments and biological substances (T36-T50) (T36–T50), under category T42, Poisoning by, adverse effect of and underdosing of antiepileptic, sedative- hypnotic and antiparkinsonism drugs.
What coding notes are listed for T42?
No inclusion terms are listed for T42 in this reference record. No code-first instruction is listed. No Excludes1 note is listed. Excludes2 notes: drug dependence and related mental and behavioral disorders due to psychoactive substance use (F10.--F19.-).