D84.821 Immunodeficiency due to drugs

Billable ICD-10-CM code, FY2026. Acts as a Complication or Comorbidity (CC) as a secondary diagnosis.

Applicable to

• Immunodeficiency due to (current or past) medication

Use additional code

• code for adverse effect if applicable, to identify adverse effect of drug (T36-T50 with fifth or six character 5)
• code, if applicable, for associated long term (current) drug therapy drug or medication such as:
• long term (current) drug therapy systemic steroids (Z79.52)
• other long term (current) drug therapy (Z79.899)

Risk adjustment (HCC)

• CMS-HCC V22: HCC 47 — Disorders of Immunity
• RxHCC V08: HCC 99 — Immune Disorders
• ESRD V24: HCC 47

MS-DRG index

Defines the logic of DRG(s) 814-816 in MDC 16.

Code annotations containing back-references to D84.821

Back-references to D84

• Type 1 Excludes: D72 Other disorders of white blood cells ("immunity disorders (D80-D89)")

Diagnosis Index entries for D84.821

• Immunodeficiency › due to › drugs
• Immunodeficiency › due to › medication (current or past)

Nearby codes

• D84.0 Lymphocyte function antigen-1 [LFA-1] defect
• D84.1 Defects in the complement system
• D84.8 Other specified immunodeficiencies
• D84.81 Immunodeficiency due to conditions classified elsewhere
• D84.82 Immunodeficiency due to drugs and external causes
• D84.821 Immunodeficiency due to drugs (this code)
• D84.822 Immunodeficiency due to external causes
• D84.89 Other immunodeficiencies
• D84.9 Immunodeficiency, unspecified