G99.0 ICD-10-CM Code: Autonomic neuropathy in diseases classified elsewhere

G99.0 is the ICD-10-CM diagnosis code for autonomic neuropathy in diseases classified elsewhere. This code describes damage to the nerves that control automatic body functions (like heart rate, blood pressure, and digestion) that occurs as a complication of another disease. It is used when autonomic nerve damage is secondary to an underlying condition rather than a primary disorder. G99.0 sits in the ICD-10-CM chapter for diseases of the nervous system (g00-g99), within the section covering other disorders of the nervous system (g89-g99).

G99.0 is a billable ICD-10-CM code but does not map to a payment HCC under the CMS-HCC V28, V24, ESRD, or RxHCC risk adjustment models. It can be reported on Medicare Advantage encounter data submissions but it does not contribute to a beneficiary's RAF score and therefore does not affect risk-adjusted payments to the plan.

This is a secondary diagnosis code that requires an underlying condition code to be reported first; identify the primary disease causing the autonomic neuropathy (such as diabetes, amyloidosis, or Parkinson's disease).