Autonomic Nervous System Function Testing

Section: Diagnostic Medical
Effective Date: May 01, 2020
Revised Date: March 16, 2020
Last Reviewed: March 16, 2020


Autonomic Nervous System (ANS) Function Tests are generally indicated to diagnose a condition, to provide unique differential diagnostic information, or to quantify those aspects of autonomic function that have an impact on outcome or evaluate treatment efficacy. Autonomic nervous system function testing consists of a battery of calibrated tests that provide an accurate assessment of the status of different parts of the autonomic nervous system.


ANS testing, consisting of a battery of tests in several domains may be considered medically necessary when ALL of the following criteria are met:

  • Signs and/or symptoms of autonomic dysfunction are present; and
  • A definitive diagnosis cannot be made from clinical examination and routine laboratory testing alone; and
  • Diagnosis of the suspected autonomic disorder will lead to a change in management or will eliminate the need for further testing.

Although there is no standard battery of tests for ANS testing, a full battery generally consists of individual tests in three (3) categories:

  • Cardiovagal function (heart rate variability, heart rate response to deep breathing and Valsalva maneuver)
  • Vasomotor adrenergic function (blood pressure response to standing, Valsalva maneuver, hand grip, and tilt table testing)
  • Sudomotor function (Quantitative Sudomotor Axon Reflex Test, quantitative sensory test, Thermoregulatory Sweat Test, silastic sweat imprint, sympathetic skin response, electrochemical sweat conductance)

NOTE: At least one (1) test in each category is usually performed. More than one (1) test from a category will often be included in a battery of test, but the incremental value of using multiple tests in a category is unknown.

The following tests are considered not medically necessary:

  • Pupil edge light cycle
  • Gastric emptying tests
  • Cold pressor test
  • Quantitative direct and indirect testing of sudomotor function test
  • Plasma catecholamine levels
  • Skin vasomotor testing

Procedure Codes

95921 95922 95923 95924 95943

ANS testing is considered experimental/investigation (E/I) and therefore non-covered for the following conditions because the safety and/or effectiveness of this service cannot be established by the available published peer-reviewed literature:

  • Chronic fatigue syndrome
  • Quantitative pupillometry
  • Fibromyalgia
  • Anxiety and other psychological disorders
  • Sleep apnea
  • Allergic conditions
  • Hypertension
  • Screening of asymptomatic individuals
  • Monitoring progression of disease or response to treatment
  • Detoxification/relaxation
  • Autonomic nervous system testing using portable automated devices (e.g., ANSAR® test)

ANS testing not meeting the above criteria is considered not medically necessary.

Procedure Codes



ANS testing should be performed in a dedicated ANS testing laboratory. Testing in a dedicated laboratory should be performed under closely controlled conditions, and results should be interpreted by an individual with expertise in ANS testing. Testing using automated devices with results interpreted by computer software has not been validated and thus has the potential to lead to erroneous results.

Diagnosis Codes

Covered Diagnosis Codes for procedure codes 95921, 95922, 95923, 95924, and 95943.

E10.40 E10.41 E10.42 E10.43 E10.44 E10.49 E10.610
E11.40 E11.41 E11.42 E11.43 E11.44 E11.49 E11.610
E13.40 E13.41 E13.42 E13.43 E13.44 E13.49 E13.610
E85.0 E85.1 E85.2 E85.3 E85.4 E85.81 E85.82
E85.89 E85.9 G23.0 G23.1 G23.2 G23.8 G23.9
G60.0 G60.3 G60.8 G60.9 G61.0 G61.1 G61.81
G61.89 G90.09 G90.2 G90.3 G90.4 G90.50 G90.511
G90.512 G90.513 G90.519 G90.521 G90.522 G90.523 G90.529
G90.59 G90.9 I95.1 M35.04 R00.0 R55

Professional Statements and Societal Positions Guidelines

Not Applicable

ND Committee Review

Internal Medical Policy Committee 3-16-2020 Coding update only


Current medical policy is to be used in determining a Member's contract benefits on the date that services are rendered. Contract language, including definitions and specific inclusions/exclusions, as well as state and federal law, must be considered in determining eligibility for coverage. Members must consult their applicable benefit plans or contact a Member Services representative for specific coverage information. Likewise, medical policy, which addresses the issue(s) in any specific case, should be considered before utilizing medical opinion in adjudication. Medical technology is constantly evolving and the Company reserves the right to review and update medical policy periodically.