G90.9Disorder of the autonomic nervous system, unspecified

G90.9 is the ICD-10-CM diagnosis code for disorder of the autonomic nervous system, unspecified. It belongs to category G90 (disorders of autonomic nervous system), block G89-G99 (other disorders of the nervous system) and chapter 6 (diseases of the nervous system). It is billable, so it can be reported on its own for dates of service from October 1, 2026 through September 30, 2027.

Within G90, choose G90.9 (Disorder of the autonomic nervous system, unspecified) only when documentation doesn't support a more specific option: idiopathic peripheral autonomic neuropathy (G90.0), familial dysautonomia [Riley-Day] (G90.1), Horner's syndrome (G90.2), Multi-system degeneration of the autonomic nervous system (G90.3), autonomic dysreflexia (G90.4), complex regional pain syndrome I (CRPS I) (G90.5), other disorders of autonomic nervous system (G90.8), postural orthostatic tachycardia syndrome [POTS] (G90.A) and 1 more.

It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.

In MS-DRG v44.0, it is part of the grouping logic for DRG 073 (Cranial and Peripheral Nerve Disorders with MCC, relative weight 1.5779) and DRG 074 (Cranial and Peripheral Nerve Disorders without MCC, relative weight 1.0173), in MDC 01 (Diseases and Disorders of the Nervous System), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.

It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.

Before ICD-10, this condition was coded in ICD-9-CM as 337.9 (unspecified disorder of autonomic nervous system).