ICDcodes.org
FY2027

T43.226DUnderdosing of selective serotonin reuptake inhibitors, subsequent encounter

Billable

Is T43.226D billable?

Yes — T43.226D is billable for FY2027. T43.226D is a valid, billable ICD-10-CM code at the highest level of specificity in its branch. T43.226D may be submitted for encounters from October 1, 2026 through September 30, 2027.

T43.226D at a glance

CodeT43.226D
DescriptionUnderdosing of selective serotonin reuptake inhibitors, 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 T43.226D?

In T43.226D, the 7th character D means subsequent encounter. The 7th character is required for T43.226D to be a valid, complete code.

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

What Medicare edits apply to T43.226D?

The Medicare Code Editor screens inpatient claims before they are grouped. These edits name T43.226D 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 T43.226D group to?

T43.226D 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 T43.226D 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 T43.226D. T43.226D 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 T43.226D to fully describe the condition. T43.226D 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 T43.226D to fully describe the condition. T43.226D 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 T43.226D, but a patient may have both at the same time. When documentation supports it, T43.226D 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 T43.226D, but a patient may have both at the same time. When documentation supports it, T43.226D 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 T43

The conditions below are not part of T43.226D, but a patient may have both at the same time. When documentation supports it, T43.226D and the excluded code may both be reported.

  • appetite depressants (T50.5-)
  • barbiturates (T42.3-)
  • benzodiazepines (T42.4-)
  • drug dependence and related mental and behavioral disorders due to psychoactive substance use (F10.- -F19.-)
  • methaqualone (T42.6-)
  • psychodysleptics [hallucinogens] (T40.7-T40.9-)

How long has T43.226D existed?

T43.226D 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.