T43.016D — Underdosing of tricyclic antidepressants, subsequent encounter
T43.016D is a billable, specific ICD-10-CM code for underdosing of tricyclic antidepressants, subsequent encounter. It is valid for submission on a claim.
7th character "D" — subsequent encounter
The appropriate 7th character is to be added to each code from category T43
- A
- initial encounter
- D
- subsequent encounter
- S
- sequela
Excludes2 inherited from the categories above T43.016D
Also inherited, and the opposite of Excludes1: these conditions are not part of T43.016D, but a patient can have both, so you may code both.
Written on T43 — Poisoning by, adverse effect of and underdosing of psychotropic drugs, not elsewhere classified
Risk adjustment
T43.016D does not map to an HCC and does not risk-adjust under CMS-HCC V28. That is normal — most ICD-10 codes do not. It still needs to be coded correctly; it just will not move a RAF score.
Medicare coverage
T43.016D is named in 3 Medicare coverage policies — 3 listing it as supporting medical necessity. Which of them applies to you depends on your Medicare contractor, and coverage genuinely differs by state.
- A56645Billing and Coding: Controlled Substance Monitoring and Drugs of Abuse Testing
- A57473Billing and Coding: Allergy Testing
- A57473Billing and Coding: Allergy Testing
Code history
T43.016D has not changed since FY2024 — no addition, revision or deletion across the three most recent ICD-10-CM releases.
Related codes at this level
Codes that share T43.016. If T43.016D is not quite right, the correct code is usually one of these.
Questions about T43.016D
- Is T43.016D a billable ICD-10-CM code?
- Yes. T43.016D is a billable, specific ICD-10-CM code and is valid for submission on a claim.
- Where does T43.016D sit in the tabular list?
- Injury, poisoning and certain other consequences of external causes (S00-T88), in the block Poisoning by, adverse effects of and underdosing of drugs, medicaments and biological substances (T36-T50).