T42.6 — Poisoning by, adverse effect of and underdosing of other antiepileptic and sedative-hypnotic drugs
Is T42.6 billable?
No — T42.6 is a non-billable header code. T42.6 groups more specific codes and cannot be submitted on a claim. A valid ICD-10-CM code must be reported at the highest level of specificity available in its branch. Select one of the 18 billable codes beneath T42.6.
Billable codes under this header
- T42.6X1APoisoning by other antiepileptic and sedative-hypnotic drugs, accidental (unintentional), initial encounter
- T42.6X1DPoisoning by other antiepileptic and sedative-hypnotic drugs, accidental (unintentional), subsequent encounter
- T42.6X1SPoisoning by other antiepileptic and sedative-hypnotic drugs, accidental (unintentional), sequela
- T42.6X2APoisoning by other antiepileptic and sedative-hypnotic drugs, intentional self-harm, initial encounter
- T42.6X2DPoisoning by other antiepileptic and sedative-hypnotic drugs, intentional self-harm, subsequent encounter
- T42.6X2SPoisoning by other antiepileptic and sedative-hypnotic drugs, intentional self-harm, sequela
- T42.6X3APoisoning by other antiepileptic and sedative-hypnotic drugs, assault, initial encounter
- T42.6X3DPoisoning by other antiepileptic and sedative-hypnotic drugs, assault, subsequent encounter
- T42.6X3SPoisoning by other antiepileptic and sedative-hypnotic drugs, assault, sequela
- T42.6X4APoisoning by other antiepileptic and sedative-hypnotic drugs, undetermined, initial encounter
- T42.6X4DPoisoning by other antiepileptic and sedative-hypnotic drugs, undetermined, subsequent encounter
- T42.6X4SPoisoning by other antiepileptic and sedative-hypnotic drugs, undetermined, sequela
- T42.6X5AAdverse effect of other antiepileptic and sedative-hypnotic drugs, initial encounter
- T42.6X5DAdverse effect of other antiepileptic and sedative-hypnotic drugs, subsequent encounter
- T42.6X5SAdverse effect of other antiepileptic and sedative-hypnotic drugs, sequela
- T42.6X6AUnderdosing of other antiepileptic and sedative-hypnotic drugs, initial encounter
- T42.6X6DUnderdosing of other antiepileptic and sedative-hypnotic drugs, subsequent encounter
- T42.6X6SUnderdosing of other antiepileptic and sedative-hypnotic drugs, sequela
T42.6 at a glance
| Code | T42.6 |
|---|---|
| Description | Poisoning by, adverse effect of and underdosing of other antiepileptic and sedative-hypnotic drugs |
| Billable | No — header code |
| Code set | ICD-10-CM FY2027 |
| Valid for encounters | October 1, 2026 – September 30, 2027 |
Excludes1 — never code together
The conditions below can never be reported together with T42.6 on the same claim. An Excludes1 note means the two conditions cannot occur in the same patient, so reporting both is a coding error.
- poisoning by, adverse effect of and underdosing of carbamazepine (T42.1-)
Inclusion terms
Alternative wording in documentation that is classified to T42.6.
- Poisoning by, adverse effect of and underdosing of methaqualone
- Poisoning by, adverse effect of and underdosing of valproic acid
Excludes1 — never code together — inherited from T36-T50
The conditions below can never be reported together with T42.6 on the same claim. An Excludes1 note means the two conditions cannot occur in the same patient, so reporting both is a coding error.
- toxic reaction to local anesthesia in pregnancy (O29.3-)
Code first — inherited from T36-T50
The underlying condition below must be sequenced before T42.6. T42.6 describes a manifestation and cannot be the principal or first-listed diagnosis.
Use additional code — inherited from Chapter 19
Report an additional code alongside T42.6 to fully describe the condition. T42.6 is sequenced first.
- code to identify any retained foreign body, if applicable (Z18.-)
Use additional code — inherited from T36-T50
Report an additional code alongside T42.6 to fully describe the condition. T42.6 is sequenced first.
Excludes2 — not included here — inherited from Chapter 19
The conditions below are not part of T42.6, but a patient may have both at the same time. When documentation supports it, T42.6 and the excluded code may both be reported.
Excludes2 — not included here — inherited from T36-T50
The conditions below are not part of T42.6, but a patient may have both at the same time. When documentation supports it, T42.6 and the excluded code may both be reported.
Excludes2 — not included here — inherited from T42
The conditions below are not part of T42.6, but a patient may have both at the same time. When documentation supports it, T42.6 and the excluded code may both be reported.
- drug dependence and related mental and behavioral disorders due to psychoactive substance use (F10.--F19.-)
What codes fall under T42.6? (1)
How long has T42.6 existed?
T42.6 has been in ICD-10-CM since at least FY2016, the earliest fiscal year on record here.
Derived from the official order files for FY2016–FY2026. FY2017 and FY2020 publish no order file, so those years are not covered.
What other codes are in the T42 family? (8)
- T42.0Poisoning by, adverse effect of and underdosing of hydantoin derivativesnot billable
- T42.1Poisoning by, adverse effect of and underdosing of iminostilbenesnot billable
- T42.2Poisoning by, adverse effect of and underdosing of succinimides and oxazolidinedionesnot billable
- T42.3Poisoning by, adverse effect of and underdosing of barbituratesnot billable
- T42.4Poisoning by, adverse effect of and underdosing of benzodiazepinesnot billable
- T42.5Poisoning by, adverse effect of and underdosing of mixed antiepilepticsnot billable
- T42.7Poisoning by, adverse effect of and underdosing of unspecified antiepileptic and sedative-hypnotic drugsnot billable
- T42.8Poisoning by, adverse effect of and underdosing of antiparkinsonism drugs and other central muscle-tone depressantsnot billable