MCMCB Pro
T56.813A

T56.813AToxic effect of thallium, assault, initial encounter

Billable / specific codeICD-10-CM

T56.813A is a billable, specific ICD-10-CM code for toxic effect of thallium, assault, initial encounter. It is valid for submission on a claim.

7th character "A" — initial encounter

The appropriate 7th character is to be added to each code from category T56

A
initial encounter
D
subsequent encounter
S
sequela

Risk adjustment

T56.813A 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

T56.813A is named in 1 Medicare coverage policy 1 listing it as supporting medical necessity. Which of them applies to you depends on your Medicare contractor, and coverage genuinely differs by state.

  • A56612Billing and Coding: CT of the Head

Related codes at this level

Codes that share T56.813. If T56.813A is not quite right, the correct code is usually one of these.

Questions about T56.813A

Is T56.813A a billable ICD-10-CM code?
Yes. T56.813A is a billable, specific ICD-10-CM code and is valid for submission on a claim.
Where does T56.813A sit in the tabular list?
Injury, poisoning and certain other consequences of external causes (S00-T88), in the block Toxic effects of substances chiefly nonmedicinal as to source (T51-T65).
ICD-10-CMFY2026-Apr· effective April 1, 2026

Loaded directly from the CMS/NCHS ICD-10-CM public-domain release — see data sources and our editorial policy. If this page disagrees with the CMS tabular list, this page is wrong. Reference information for professional coders; not medical or billing advice.