T42
Non-Billable

Poisoning by, adverse effect of and underdosing of antiepileptic, sedative- hypnotic and antiparkinsonism drugs

Non-Billable / Non-Specific Code

What is Poisoning by, adverse effect of and underdosing of antiepileptic, sedative- hypnotic and antiparkinsonism drugs?

ICD-10-CM T42 is the diagnosis code for Poisoning by, adverse effect of and underdosing of antiepileptic, sedative- hypnotic and antiparkinsonism drugs. This code falls under the section "Poisoning by, adverse effect of and underdosing of drugs, medicaments and biological substances" within Chapter 19 — Injury, poisoning and certain other consequences of external causes (S00-T88). It is a non-billable/non-specific ICD-10-CM code that should not be used for reimbursement. A more specific sub-code is required for billing. Medical coders and healthcare providers use this code to document and classify diagnoses in electronic health records, insurance claims, and clinical databases.

â„šī¸ Excludes2

Coding Guidelines for T42

â„šī¸ Type 2 Excludes (Code separately if applicable)

The following conditions are not included in T42. If the patient has both, code each condition separately:

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

ICD-10-CM Code Hierarchy

Understanding where T42 sits in the ICD-10-CM classification helps ensure proper coding:

Current CodeT42 — Poisoning by, adverse effect of and underdosing of antiepileptic, sedative- hypnotic and antiparkinsonism drugs
Sub-Codes 9 entries
T42.0Poisoning by, adverse effect of and underdosing of hydantoin derivativesNon-BillableT42.0XPoisoning by, adverse effect of and underdosing of hydantoin derivativesNon-BillableT42.0X1Poisoning by hydantoin derivatives, accidental (unintentional)BillableT42.0X2Poisoning by hydantoin derivatives, intentional self-harmBillableT42.0X3Poisoning by hydantoin derivatives, assaultBillableT42.0X4Poisoning by hydantoin derivatives, undeterminedBillableT42.0X5Adverse effect of hydantoin derivativesBillableT42.0X6Underdosing of hydantoin derivativesBillableT42.1Poisoning by, adverse effect of and underdosing of iminostilbenesNon-BillableT42.1XPoisoning by, adverse effect of and underdosing of iminostilbenesNon-BillableT42.1X1Poisoning by iminostilbenes, accidental (unintentional)BillableT42.1X2Poisoning by iminostilbenes, intentional self-harmBillableT42.1X3Poisoning by iminostilbenes, assaultBillableT42.1X4Poisoning by iminostilbenes, undeterminedBillableT42.1X5Adverse effect of iminostilbenesBillableT42.1X6Underdosing of iminostilbenesBillableT42.2Poisoning by, adverse effect of and underdosing of succinimides and oxazolidinedionesNon-BillableT42.2XPoisoning by, adverse effect of and underdosing of succinimides and oxazolidinedionesNon-BillableT42.2X1Poisoning by succinimides and oxazolidinediones, accidental (unintentional)BillableT42.2X2Poisoning by succinimides and oxazolidinediones, intentional self-harmBillableT42.2X3Poisoning by succinimides and oxazolidinediones, assaultBillableT42.2X4Poisoning by succinimides and oxazolidinediones, undeterminedBillableT42.2X5Adverse effect of succinimides and oxazolidinedionesBillableT42.2X6Underdosing of succinimides and oxazolidinedionesBillableT42.3Poisoning by, adverse effect of and underdosing of barbituratesNon-BillableT42.3XPoisoning by, adverse effect of and underdosing of barbituratesNon-BillableT42.3X1Poisoning by barbiturates, accidental (unintentional)BillableT42.3X2Poisoning by barbiturates, intentional self-harmBillableT42.3X3Poisoning by barbiturates, assaultBillableT42.3X4Poisoning by barbiturates, undeterminedBillableT42.3X5Adverse effect of barbituratesBillableT42.3X6Underdosing of barbituratesBillableT42.4Poisoning by, adverse effect of and underdosing of benzodiazepinesNon-BillableT42.4XPoisoning by, adverse effect of and underdosing of benzodiazepinesNon-BillableT42.4X1Poisoning by benzodiazepines, accidental (unintentional)BillableT42.4X2Poisoning by benzodiazepines, intentional self-harmBillableT42.4X3Poisoning by benzodiazepines, assaultBillableT42.4X4Poisoning by benzodiazepines, undeterminedBillableT42.4X5Adverse effect of benzodiazepinesBillableT42.4X6Underdosing of benzodiazepinesBillableT42.5Poisoning by, adverse effect of and underdosing of mixed antiepilepticsNon-BillableT42.5XPoisoning by, adverse effect of and underdosing of antiepilepticsNon-BillableT42.5X1Poisoning by mixed antiepileptics, accidental (unintentional)BillableT42.5X2Poisoning by mixed antiepileptics, intentional self-harmBillableT42.5X3Poisoning by mixed antiepileptics, assaultBillableT42.5X4Poisoning by mixed antiepileptics, undeterminedBillableT42.5X5Adverse effect of mixed antiepilepticsBillableT42.5X6Underdosing of mixed antiepilepticsBillableT42.6Poisoning by, adverse effect of and underdosing of other antiepileptic and sedative-hypnotic drugsNon-BillableT42.6XPoisoning by, adverse effect of and underdosing of other antiepileptic and sedative-hypnotic drugsNon-BillableT42.6X1Poisoning by other antiepileptic and sedative-hypnotic drugs, accidental (unintentional)BillableT42.6X2Poisoning by other antiepileptic and sedative-hypnotic drugs, intentional self-harmBillableT42.6X3Poisoning by other antiepileptic and sedative-hypnotic drugs, assaultBillableT42.6X4Poisoning by other antiepileptic and sedative-hypnotic drugs, undeterminedBillableT42.6X5Adverse effect of other antiepileptic and sedative-hypnotic drugsBillableT42.6X6Underdosing of other antiepileptic and sedative-hypnotic drugsBillableT42.7Poisoning by, adverse effect of and underdosing of unspecified antiepileptic and sedative-hypnotic drugsNon-BillableT42.71Poisoning by unspecified antiepileptic and sedative-hypnotic drugs, accidental (unintentional)BillableT42.72Poisoning by unspecified antiepileptic and sedative-hypnotic drugs, intentional self-harmBillableT42.73Poisoning by unspecified antiepileptic and sedative-hypnotic drugs, assaultBillableT42.74Poisoning by unspecified antiepileptic and sedative-hypnotic drugs, undeterminedBillableT42.75Adverse effect of unspecified antiepileptic and sedative-hypnotic drugsBillableT42.76Underdosing of unspecified antiepileptic and sedative-hypnotic drugsBillableT42.8Poisoning by, adverse effect of and underdosing of antiparkinsonism drugs and other central muscle-tone depressantsNon-BillableT42.8XPoisoning by, adverse effect of and underdosing of antiparkinsonism drugs and other central muscle-tone depressantsNon-BillableT42.8X1Poisoning by antiparkinsonism drugs and other central muscle-tone depressants, accidental (unintentional)BillableT42.8X2Poisoning by antiparkinsonism drugs and other central muscle-tone depressants, intentional self-harmBillableT42.8X3Poisoning by antiparkinsonism drugs and other central muscle-tone depressants, assaultBillableT42.8X4Poisoning by antiparkinsonism drugs and other central muscle-tone depressants, undeterminedBillableT42.8X5Adverse effect of antiparkinsonism drugs and other central muscle-tone depressantsBillableT42.8X6Underdosing of antiparkinsonism drugs and other central muscle-tone depressantsBillable
Related Codes

Frequently Asked Questions

Is T42 a billable ICD-10-CM code?

No, T42 is a non-billable/non-specific code. You should use a more specific sub-code for billing and reimbursement.

What does T42 mean?

T42 is the ICD-10-CM diagnosis code for "Poisoning by, adverse effect of and underdosing of antiepileptic, sedative- hypnotic and antiparkinsonism drugs". It is used by healthcare providers to classify and document this condition in medical records and insurance claims.

What section is T42 in?

T42 is located in Section T36-T50 — "Poisoning by, adverse effect of and underdosing of drugs, medicaments and biological substances" within Chapter 19 of the ICD-10-CM Tabular List.

What are the sub-codes of T42?

T42 has 9 sub-code(s) that provide more specific detail: T42.0, T42.1, T42.2, T42.3, T42.4 and more.

When should I use T42?

Use T42 when the patients documented diagnosis matches "Poisoning by, adverse effect of and underdosing of antiepileptic, sedative- hypnotic and antiparkinsonism drugs" and the clinical documentation supports this level of specificity. Always verify with the latest ICD-10-CM guidelines and payer requirements.

People Also Ask

What is the ICD-10 code for Poisoning by, adverse effect of and underdosing of antiepileptic, sedative- hypnotic and antiparkinsonism drugs?

The ICD-10-CM code for Poisoning by, adverse effect of and underdosing of antiepileptic, sedative- hypnotic and antiparkinsonism drugs is T42.

Can T42 be used for primary diagnosis?

No, T42 is non-billable. Use a more specific sub-code for primary diagnosis billing.

What chapter is T42 in?

T42 is in Chapter 19 of the ICD-10-CM Tabular List.

Is T42 valid for 2026?

Yes, T42 is a valid ICD-10-CM code for the 2026 fiscal year, subject to official CMS updates.

See Also

← PreviousT41.5X6Underdosing of therapeutic gasesNext →T42.0Poisoning by, adverse effect of and underdosing of hydantoin derivatives
Code Details
T42
Poisoning by, adverse effect of and underdosing of antiepileptic, sedative- hypnotic and antiparkinsonism drugs
Non-Billable / Non-Specific Code
19 — Injury, poisoning and certain other consequences of external causes (S00-T88)
T36-T50 — Poisoning by, adverse effect of and underdosing of drugs, medicaments and biological substances
2026 ICD-10-CM