ICDcodes.org
FY2027

T50.Z16DUnderdosing of immunoglobulin, subsequent encounter

Billable

Is T50.Z16D billable?

Yes — T50.Z16D is billable for FY2027. T50.Z16D is a valid, billable ICD-10-CM code at the highest level of specificity in its branch. T50.Z16D may be submitted for encounters from October 1, 2026 through September 30, 2027.

T50.Z16D at a glance

CodeT50.Z16D
DescriptionUnderdosing of immunoglobulin, subsequent encounter
BillableYes
Code setICD-10-CM FY2027
Valid for encountersOctober 1, 2026 – September 30, 2027
7th character "D"subsequent encounter

What does the 7th character "D" mean in T50.Z16D?

In T50.Z16D, the 7th character D means subsequent encounter. The 7th character is required for T50.Z16D to be a valid, complete code.

Same condition, different episode of care — switch the 7th character:

What Medicare edits apply to T50.Z16D?

The Medicare Code Editor screens inpatient claims before they are grouped. These edits name T50.Z16D directly.

Cannot be a principal diagnosis — MCE edit 9

CMS will reject this code as the principal diagnosis on an inpatient claim. It describes something other than the condition chiefly responsible for the admission.

Which MS-DRGs does T50.Z16D group to?

T50.Z16D sits in MDC 23 and helps define the logic of 2 MS-DRGs (version 44, FY2027). Which one a stay actually groups to also depends on procedures and secondary diagnoses.

  • 949Aftercare with CC/MCCmedical
  • 950Aftercare without CC/MCCmedical

Excludes1 — never code together — inherited from T36-T50

The conditions below can never be reported together with T50.Z16D 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 T50.Z16D. T50.Z16D 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 T50.Z16D to fully describe the condition. T50.Z16D 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 T50.Z16D to fully describe the condition. T50.Z16D 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 T50.Z16D, but a patient may have both at the same time. When documentation supports it, T50.Z16D 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 T50.Z16D, but a patient may have both at the same time. When documentation supports it, T50.Z16D 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)

How long has T50.Z16D existed?

T50.Z16D 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.