G90 Disorders of autonomic nervous system

Category / Non-billable header 26 subcodes

Block: Other disorders of the nervous system (G89-G99)

Excludes 1 (cannot be coded together)

  • dysfunction of the autonomic nervous system due to alcohol (G31.2)

Subcodes

Each subcode links to a detail page with full clinical annotations.

Code Description Billable
G90..0 Idiopathic peripheral autonomic neuropathy No
G90..01 Carotid sinus syncope Yes
G90..09 Other idiopathic peripheral autonomic neuropathy Yes
G90..1 Familial dysautonomia [Riley-Day] Yes
G90..2 Horner's syndrome Yes
G90..3 Multi-system degeneration of the autonomic nervous system Yes
G90..4 Autonomic dysreflexia Yes
G90..5 Complex regional pain syndrome I (CRPS I) No
G90..50 Complex regional pain syndrome I, unspecified Yes
G90..51 Complex regional pain syndrome I of upper limb No
G90..511 Complex regional pain syndrome I of right upper limb Yes
G90..512 Complex regional pain syndrome I of left upper limb Yes
G90..513 Complex regional pain syndrome I of upper limb, bilateral Yes
G90..519 Complex regional pain syndrome I of unspecified upper limb Yes
G90..52 Complex regional pain syndrome I of lower limb No
G90..521 Complex regional pain syndrome I of right lower limb Yes
G90..522 Complex regional pain syndrome I of left lower limb Yes
G90..523 Complex regional pain syndrome I of lower limb, bilateral Yes
G90..529 Complex regional pain syndrome I of unspecified lower limb Yes
G90..59 Complex regional pain syndrome I of other specified site Yes
G90..8 Other disorders of autonomic nervous system No
G90..81 Serotonin syndrome Yes
G90..89 Other disorders of autonomic nervous system Yes
G90..9 Disorder of the autonomic nervous system, unspecified Yes
G90..A Postural orthostatic tachycardia syndrome [POTS] Yes
G90..B LMNB1-related autosomal dominant leukodystrophy Yes

Last reviewed: September 2026