MCMCB Pro
T88.1XXS

T88.1XXSOther complications following immunization, not elsewhere classified, sequela

Billable / specific codeICD-10-CMPOA exempt

T88.1XXS is a billable, specific ICD-10-CM code for other complications following immunization, not elsewhere classified, sequela. It is valid for submission on a claim.

7th character "S" — sequela

The appropriate 7th character is to be added to each code from category T88

A
initial encounter
D
subsequent encounter
S
sequela

Excludes1 — never code together

These conditions cannot occur together. Billing both on the same encounter is a denial.

  • vaccinia not from vaccine (B08.011)

Excludes2 — not included here, but may coexist

The excluded condition is not part of this code, but a patient can have both. You may code both.

  • anaphylactic shock due to serum (T80.5-)
  • other serum reactions (T80.6-)
  • postimmunization arthropathy (M02.2)
  • postimmunization encephalitis (G04.02)
  • postimmunization fever (R50.83)

Inclusion terms

Alternative wordings a physician may use in the chart for this same code.

  • Generalized vaccinia
  • Rash following immunization

Risk adjustment

T88.1XXS 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

T88.1XXS is named in 5 Medicare coverage policies 5 listing it as supporting medical necessity. Which of them applies to you depends on your Medicare contractor, and coverage genuinely differs by state.

  • A53057Billing and Coding: Home Health Occupational Therapy
  • A53058Billing and Coding: Home Health Physical Therapy
  • A53065Billing and Coding: Outpatient Physical Therapy
  • A56559Billing and Coding: Allergy Skin Testing

Related codes at this level

Codes that share T88.1. If T88.1XXS is not quite right, the correct code is usually one of these.

Questions about T88.1XXS

Is T88.1XXS a billable ICD-10-CM code?
Yes. T88.1XXS is a billable, specific ICD-10-CM code and is valid for submission on a claim.
Where does T88.1XXS sit in the tabular list?
Injury, poisoning and certain other consequences of external causes (S00-T88), in the block Complications of surgical and medical care, not elsewhere classified (T80-T88).
What cannot be coded together with T88.1XXS?
T88.1XXS carries an Excludes1 note, which means the conditions it lists can never be coded together with it on the same encounter.
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.