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T88.1

T88.1Other complications following immunization, not elsewhere classified

Non-billable headerICD-10-CM

T88.1 is a non-billable header ICD-10-CM code for other complications following immunization, not elsewhere classified. It cannot be billed on its own: choose one of the more specific child codes below. This code also requires a 7th character before it is complete.

This code requires a 7th character

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

Other codes that can never be billed with T88.1

These codes carry an Excludes1 note pointing at T88.1. The conflict binds both ways, but ICD-10-CM only writes it down on one side — so you would not find this by reading T88.1 alone.

Risk adjustment

T88.1 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.

How T88.1 is indexed

Coders do not find codes by browsing the tabular list — they look them up in the alphabetic index, under the word the physician wrote. These are the index entries that lead here, so you can see which chart wordings map to T88.1.

  • Vaccinia(generalized) (localized)
  • Complicationvaccination
  • Cowpoxdue to vaccination
  • Eczemavaccination, vaccinatum
  • Rashfollowing immunization
  • Complicationvaccinationrash
  • Complicationvaccinationreaction(allergic)
  • Complicationvaccinationvaccinia(generalized) (localized)
  • Kaposi'svaricelliform eruptionvaccinia

Code to one of these instead T88.1

3 child codes. Green means billable.

Related codes at this level

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

Questions about T88.1

Is T88.1 a billable ICD-10-CM code?
No. T88.1 is a non-billable header code. Code to a higher level of specificity using one of its child codes.
Where does T88.1 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 T88.1?
T88.1 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.