T43.616A — Underdosing of caffeine, initial encounter
Is T43.616A billable?
Yes — T43.616A is billable for FY2027. T43.616A is a valid, billable ICD-10-CM code at the highest level of specificity in its branch. T43.616A may be submitted for encounters from October 1, 2026 through September 30, 2027.
T43.616A at a glance
| Code | T43.616A |
|---|---|
| Description | Underdosing of caffeine, initial encounter |
| Billable | Yes |
| Code set | ICD-10-CM FY2027 |
| Valid for encounters | October 1, 2026 – September 30, 2027 |
| 7th character "A" | initial encounter |
What does the 7th character "A" mean in T43.616A?
In T43.616A, the 7th character A means initial encounter. The 7th character is required for T43.616A to be a valid, complete code.
Same condition, different episode of care — switch the 7th character:
What Medicare edits apply to T43.616A?
The Medicare Code Editor screens inpatient claims before they are grouped. These edits name T43.616A directly.
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 T43.616A group to?
T43.616A sits in MDC 23 and helps define the logic of 1 MS-DRG (version 44, FY2027). Which one a stay actually groups to also depends on procedures and secondary diagnoses.
- 951Other Factors Influencing Health Statusmedical
Excludes1 — never code together — inherited from T36-T50
The conditions below can never be reported together with T43.616A 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 T43.6
The conditions below can never be reported together with T43.616A 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 cocaine (T40.5-)
Code first — inherited from T36-T50
The underlying condition below must be sequenced before T43.616A. T43.616A describes a manifestation and cannot be the principal or first-listed diagnosis.
Use additional code — inherited from Chapter 19
Report an additional code alongside T43.616A to fully describe the condition. T43.616A 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 T43.616A to fully describe the condition. T43.616A is sequenced first.
Excludes2 — not included here — inherited from Chapter 19
The conditions below are not part of T43.616A, but a patient may have both at the same time. When documentation supports it, T43.616A and the excluded code may both be reported.
Excludes2 — not included here — inherited from T36-T50
The conditions below are not part of T43.616A, but a patient may have both at the same time. When documentation supports it, T43.616A and the excluded code may both be reported.
Excludes2 — not included here — inherited from T43
The conditions below are not part of T43.616A, but a patient may have both at the same time. When documentation supports it, T43.616A and the excluded code may both be reported.
How long has T43.616A existed?
T43.616A 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.