ICDcodes.org
FY2027

T42.4X6 — Underdosing of benzodiazepines

Not billable

Is T42.4X6 billable?

No — T42.4X6 is a non-billable header code. T42.4X6 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 T42.4X6.

T42.4X6 at a glance

CodeT42.4X6
DescriptionUnderdosing of benzodiazepines
BillableNo — header code
Code setICD-10-CM FY2027
Valid for encountersOctober 1, 2026 – September 30, 2027

Excludes1 — never code together — inherited from T36-T50

The conditions below can never be reported together with T42.4X6 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 T42.4X6. T42.4X6 describes a manifestation and cannot be the principal or first-listed diagnosis.

  • , for adverse effects, the nature of the adverse effect, such as:
  • adverse effect NOS (T88.7)
  • aspirin gastritis (K29.-)
  • blood disorders (D56-D76)
  • contact dermatitis (L23-L25)
  • dermatitis due to substances taken internally (L27.-)
  • nephropathy (N14.0-N14.2)

Use additional code — inherited from Chapter 19

Report an additional code alongside T42.4X6 to fully describe the condition. T42.4X6 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 T42.4X6 to fully describe the condition. T42.4X6 is sequenced first.

  • code(s) to specify:
  • manifestations of poisoning
  • underdosing or failure in dosage during medical and surgical care (Y63.6, Y63.8-Y63.9)
  • underdosing of medication regimen (Z91.12-, Z91.13-)

Excludes2 — not included here — inherited from Chapter 19

The conditions below are not part of T42.4X6, but a patient may have both at the same time. When documentation supports it, T42.4X6 and the excluded code may both be reported.

  • birth trauma (P10-P15)
  • obstetric trauma (O70-O71)

Excludes2 — not included here — inherited from T36-T50

The conditions below are not part of T42.4X6, but a patient may have both at the same time. When documentation supports it, T42.4X6 and the excluded code may both be reported.

  • abuse and dependence of psychoactive substances (F10-F19)
  • abuse of non-dependence-producing substances (F55.-)
  • immunodeficiency due to drugs (D84.821)
  • drug reaction and poisoning affecting newborn (P00-P96)
  • pathological drug intoxication (inebriation) (F10-F19)

Excludes2 — not included here — inherited from T42

The conditions below are not part of T42.4X6, but a patient may have both at the same time. When documentation supports it, T42.4X6 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 T42.4X6? (3)

How long has T42.4X6 existed?

T42.4X6 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 T42.4X family? (5)