T42.6X6 — Underdosing of other antiepileptic and sedative-hypnotic drugs
Is T42.6X6 billable?
No — T42.6X6 is a non-billable header code. T42.6X6 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 3 billable codes beneath T42.6X6.
T42.6X6 at a glance
| Code | T42.6X6 |
|---|---|
| Description | 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 — inherited from T36-T50
The conditions below can never be reported together with T42.6X6 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-)
Excludes1 — never code together — inherited from T42.6
The conditions below can never be reported together with T42.6X6 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-)
Code first — inherited from T36-T50
The underlying condition below must be sequenced before T42.6X6. T42.6X6 describes a manifestation and cannot be the principal or first-listed diagnosis.
Use additional code — inherited from Chapter 19
Report an additional code alongside T42.6X6 to fully describe the condition. T42.6X6 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 T42.6X6 to fully describe the condition. T42.6X6 is sequenced first.
Excludes2 — not included here — inherited from Chapter 19
The conditions below are not part of T42.6X6, but a patient may have both at the same time. When documentation supports it, T42.6X6 and the excluded code may both be reported.
Excludes2 — not included here — inherited from T36-T50
The conditions below are not part of T42.6X6, but a patient may have both at the same time. When documentation supports it, T42.6X6 and the excluded code may both be reported.
Excludes2 — not included here — inherited from T42
The conditions below are not part of T42.6X6, but a patient may have both at the same time. When documentation supports it, T42.6X6 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 T42.6X6? (3)
How long has T42.6X6 existed?
T42.6X6 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 T42.6X family? (5)
- T42.6X1Poisoning by other antiepileptic and sedative-hypnotic drugs, accidental (unintentional)not billable
- T42.6X2Poisoning by other antiepileptic and sedative-hypnotic drugs, intentional self-harmnot billable
- T42.6X3Poisoning by other antiepileptic and sedative-hypnotic drugs, assaultnot billable
- T42.6X4Poisoning by other antiepileptic and sedative-hypnotic drugs, undeterminednot billable
- T42.6X5Adverse effect of other antiepileptic and sedative-hypnotic drugsnot billable