G90.2
Horner's syndrome
Billable FY2026 2025-10-01 → 2026-09-30
Exclusions 9 never code together
G00-G99chapter
Excludes2
- certain conditions originating in the perinatal period (P04-P96)P04-P96
- certain infectious and parasitic diseases (A00-B99)A00-B99
- complications of pregnancy, childbirth and the puerperium (O00-O9A)O00-O9A
- congenital malformations, deformations, and chromosomal abnormalities (Q00-Q99)Q00-Q99
- endocrine, nutritional and metabolic diseases (E00-E88)E00-E88
- injury, poisoning and certain other consequences of external causes (S00-T88)S00-T88
- neoplasms (C00-D49)C00-D49
- symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)R00-R94
Excludes1 — never code together. The excluded condition and this one are mutually exclusive.
Excludes2 — not included here, but the patient may have both. Code both when documented.
Instructional notes 2
G90.2code
Inclusion terms
- Bernard(-Horner) syndrome
- Cervical sympathetic dystrophy or paralysis
Index entries leading here 5
Alongside this code 9 same parent — G90
G90.0 Idiopathic peripheral autonomic neuropathy category G90.1 Familial dysautonomia [Riley-Day] G90.3 Multi-system degeneration of the autonomic nervous system G90.4 Autonomic dysreflexia G90.5 Complex regional pain syndrome I (CRPS I) category G90.8 Other disorders of autonomic nervous system category G90.9 Disorder of the autonomic nervous system, unspecified G90.A Postural orthostatic tachycardia syndrome [POTS] G90.B LMNB1-related autosomal dominant leukodystrophy
Additional references
AHA Coding Clinic® Licence required
Official coding advice for this code. Published by the American Hospital Association. Not included in this installation.