G90.50 Complex regional pain syndrome I, unspecified

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

Applies from G90 Disorders of autonomic nervous system

Excludes1 (never code together)

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

Applies from G90.5 Complex regional pain syndrome I (CRPS I)

Applicable to

• Reflex sympathetic dystrophy

Excludes1 (never code together)

• causalgia of lower limb (G57.7-)
• causalgia of upper limb (G56.4-)
• complex regional pain syndrome II of lower limb (G57.7-)
• complex regional pain syndrome II of upper limb (G56.4-)

MS-DRG index

Defines the logic of DRG(s) 073-074 in MDC 01.

Approximate ICD-9-CM (GEMs)

• 337.20 Reflex sympathetic dystrophy, unspecified (approximate)

Medicare Code Edits (MCE v43.1 (April 2026))

• Unspecified code (laterality): Unspecified codes for which a more specific code identifying laterality (right, left, bilateral) exists within the same code family.

Code annotations containing back-references to G90.50

Back-references to G90.5

• Type 1 Excludes: G89.2 Chronic pain, not elsewhere classified ("reflex sympathetic dystrophy (G90.5-)")
• Type 1 Excludes: M89.0 Algoneurodystrophy ("reflex sympathetic dystrophy (G90.5-)")

Diagnosis Index entries for G90.50

• Syndrome › pain › complex regional I

Nearby codes

• G90.1 Familial dysautonomia [Riley-Day]
• G90.2 Horner's syndrome
• G90.3 Multi-system degeneration of the autonomic nervous system
• G90.4 Autonomic dysreflexia
• G90.5 Complex regional pain syndrome I (CRPS I)
• G90.50 Complex regional pain syndrome I, unspecified (this code)
• G90.51 Complex regional pain syndrome I of upper limb
• G90.511 Complex regional pain syndrome I of right upper limb
• G90.512 Complex regional pain syndrome I of left upper limb
• G90.513 Complex regional pain syndrome I of upper limb, bilateral
• G90.519 Complex regional pain syndrome I of unspecified upper limb