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Official Description

Vasopressin (antidiuretic hormone, ADH)

© Copyright 2026 American Medical Association. All rights reserved.

Common Language Description

The CPT® Code 84588 refers to a laboratory test that measures the levels of arginine vasopressin, also known as antidiuretic hormone (ADH), in the blood. This hormone plays a crucial role in the regulation of water balance, glucose, and sodium levels within the bloodstream. Synthesized in the hypothalamus, ADH is stored in the posterior pituitary gland until it is released into the bloodstream in response to specific physiological conditions, particularly dehydration. When the body experiences a lack of water, ADH is secreted to prompt the kidneys to conserve water, thereby concentrating urine and reducing urine volume. Additionally, ADH contributes to the regulation of blood pressure by increasing peripheral vascular resistance through vasoconstriction, which can lead to elevated blood pressure levels. The test involves obtaining a blood sample through a procedure known as venipuncture, which is separately reportable. The plasma obtained from the blood sample is then analyzed using a quantitative radioimmunoassay method to determine the concentration of vasopressin present.

© Copyright 2026 Coding Ahead. All rights reserved.

1. Indications

The vasopressin (antidiuretic hormone, ADH) test, coded as CPT® 84588, is indicated for the evaluation of various clinical conditions related to fluid balance and hormonal regulation. The following are specific indications for performing this test:

  • Assessment of Diabetes Insipidus This test is utilized to help differentiate between central diabetes insipidus, which is due to insufficient production of ADH, and nephrogenic diabetes insipidus, where the kidneys do not respond to ADH.
  • Evaluation of Hyponatremia The test aids in determining the cause of low sodium levels in the blood, which can be influenced by abnormal ADH secretion.
  • Monitoring of ADH Levels It is used to monitor patients with conditions that may affect ADH secretion, such as certain tumors or after head injuries.

2. Procedure

The procedure for obtaining the vasopressin level involves several key steps that ensure accurate measurement of the hormone in the blood. The following outlines the procedural steps:

  • Step 1: Patient Preparation Prior to the blood draw, the patient may be instructed to fast or avoid certain medications that could interfere with the test results. It is essential to ensure that the patient is adequately hydrated unless otherwise specified by the healthcare provider.
  • Step 2: Venipuncture A qualified healthcare professional performs venipuncture to collect a blood sample. This involves cleaning the skin over the chosen vein with an antiseptic, applying a tourniquet to engorge the vein, and inserting a needle to draw blood into a collection tube. The blood sample must be handled carefully to prevent hemolysis, which could affect the test results.
  • Step 3: Plasma Separation After collection, the blood sample is processed to separate the plasma from the cellular components. This is typically done by centrifugation, which spins the sample at high speed to separate the components based on density.
  • Step 4: Quantitative Radioimmunoassay The separated plasma is then subjected to a quantitative radioimmunoassay, a laboratory technique that uses radioactively labeled antibodies to measure the concentration of vasopressin in the plasma. This method provides precise quantification of the hormone levels.

3. Post-Procedure

After the blood sample has been collected and processed, there are generally no specific post-procedure care requirements for the patient. However, it is advisable for the patient to remain hydrated and to monitor the venipuncture site for any signs of complications, such as excessive bleeding or bruising. The results of the vasopressin test will be interpreted by the healthcare provider in conjunction with the patient's clinical history and other laboratory findings to make informed decisions regarding diagnosis and treatment.

Short Descr ASSAY OF VASOPRESSIN
Medium Descr ASSAY OF VASOPRESSIN ANTI-DIURETIC HORMONE
Long Descr Vasopressin (antidiuretic hormone, ADH)
Status Code Statutory Exclusion (from MPFS, may be paid under other methodologies)
Global Days XXX - Global Concept Does Not Apply
PC/TC Indicator (26, TC) 9 - Not Applicable
Multiple Procedures (51) 9 - Concept does not apply.
Bilateral Surgery (50) 9 - Concept does not apply.
Physician Supervisions 09 - Concept does not apply.
Assistant Surgeon (80, 82) 9 - Concept does not apply.
Co-Surgeons (62) 9 - Concept does not apply.
Team Surgery (66) 9 - Concept does not apply.
Diagnostic Imaging Family 99 - Concept Does Not Apply
CLIA Waived (QW) No
APC Status Indicator Conditionally packaged laboratory tests
Type of Service (TOS) 5 - Diagnostic Laboratory
Berenson-Eggers TOS (BETOS) T1H - Lab tests - other (non-Medicare fee schedule)
MUE 1
CCS Clinical Classification 233 - Laboratory - Chemistry and Hematology
90 Reference (outside) laboratory: when laboratory procedures are performed by a party other than the treating or reporting physician or other qualified health care professional, the procedure may be identified by adding modifier 90 to the usual procedure number.
91 Repeat clinical diagnostic laboratory test: in the course of treatment of the patient, it may be necessary to repeat the same laboratory test on the same day to obtain subsequent (multiple) test results. under these circumstances, the laboratory test performed can be identified by its usual procedure number and the addition of modifier 91. note: this modifier may not be used when tests are rerun to confirm initial results; due to testing problems with specimens or equipment; or for any other reason when a normal, one-time, reportable result is all that is required. this modifier may not be used when other code(s) describe a series of test results (eg, glucose tolerance tests, evocative/suppression testing). this modifier may only be used for laboratory test(s) performed more than once on the same day on the same patient.
Q4 Service for ordering/referring physician qualifies as a service exemption
QJ Services/items provided to a prisoner or patient in state or local custody, however the state or local government, as applicable, meets the requirements in 42 cfr 411.4 (b)
Date
Action
Notes
2013-01-01 Changed Medium Descriptor changed.
Pre-1990 Added Code added.
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