T46.1 — Poisoning by, adverse effect of and underdosing of calcium-channel blockers

Not billable

Is T46.1 billable?

No — T46.1 is a non-billable header code. T46.1 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 T46.1.

Billable codes under this header

T46.1 at a glance

Code	T46.1
Description	Poisoning by, adverse effect of and underdosing of calcium-channel blockers
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 T46.1 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 T46

The conditions below can never be reported together with T46.1 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 metaraminol (T44.4)

Code first — inherited from T36-T50

The underlying condition below must be sequenced before T46.1. T46.1 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 T46.1 to fully describe the condition. T46.1 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 T46.1 to fully describe the condition. T46.1 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 T46.1, but a patient may have both at the same time. When documentation supports it, T46.1 and the excluded code may both be reported.

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

Excludes2 — not included here — inherited from T36-T50