Loading...

    Explore
    • Policy Monitoring
    • Live Policy Feed
    • Billing Codes
    • NPI Medicare & Medicaid
    • Healthcare Providers
    • Health Insurance Payers
    • States
    • Service Lines
    • Taxonomy Codes
    Lookup tools
    • Billing Code Lookup
    • CPT Modifier Lookup
    • Provider Taxonomy Code Lookup
    • Healthcare Provider & Facility Lookup
    • Health Insurance Payer Lookup
    • Payer Contact Directory

    Policy & Benchmark Tools

    • Prior Authorization Lookup
    • Coverage Criteria Lookup
    • Timely Filing Lookup
    • Billing Code Reimbursement Rates
    • Payer Comparison Dashboard
    • Facility Comparison Dashboard
    • All tools

    Company

    • About OpenPayer
    • Data Sources
    • Trek Health
    OpenPayerby Trek Health
    LinkedInYouTube

    © 2026 Trek Health. All rights reserved.

    OpenPayer is built and maintained by Trek Health.

    v1.0.30
    OpenPayerBilling CodesEvocative/Suppression Testing ProceduresCPT cpt-80400-acth-stimulation-test-adrenal-function
    Ask Trek AI about this page

    CPT 80400: ACTH Stimulation Test for Adrenal Function

    CPT code 80400 describes an ACTH stimulation test used to evaluate adrenal gland function by measuring cortisol response after administration of synthetic adrenocorticotropic hormone; the service is a diagnostic endocrine stimulation test typically performed in an outpatient clinic, endocrinology office, or hospital outpatient department with specimen collection and laboratory cortisol measurements.

    For related coverage guidance, see recent payer policy updates: Diabetic Supplies, Radiofrequency Ablation for Thyroid Nodules, Continuous Glucose Monitoring and Insulin Delivery for Managing Diabetes (for Idaho Only).

    Customize your policy alerts

    Sign up for cpt 80400 policy alerts

    Get alerted when payer policies referencing 80400 are released or updated.

    Monitor payer policy activity

    Receive email alerts as soon as relevant payer policies are published or updated.

    Table of contents

    Progress1 / 7

    Explore openpayer tools

    • Billing CodesCPT, HCPCS, DRG & more
    • Reimbursement RatesCommercial vs. Medicare rate reports
    • Facility ComparisonBeds, revenue & payer mix
    • ProvidersHospitals & facilities
    • PayersPlans & market footprint
    • Taxonomy CodesNUCC specialty codes
    • ModifiersCPT modifiers & usage
    • Prior AuthorizationPA policies by payer & drug
    • Timely FilingFiling deadlines by payer
    • Coverage CriteriaMedical necessity by payer
    • Payer ContactsClaims, PA & appeals contacts
    View all tools

    Clinical & Coding Specifications

    Clinical Context

    A typical patient is a 45-year-old female referred to endocrinology for evaluation of suspected primary or secondary adrenal insufficiency after episodes of unexplained fatigue, hypotension, weight loss, and persistent hyponatremia. The endocrinologist reviews history, medications (including chronic corticosteroid use or recent steroid withdrawal), and orders an ACTH stimulation test (80400) to assess adrenal cortisol reserve. The patient arrives fasting in the outpatient infusion or procedure area. Baseline blood is drawn for serum cortisol (and often plasma ACTH). Synthetic adrenocorticotropic hormone (cosyntropin) is administered intravenously or intramuscularly per protocol. Timed post‑dose blood samples are taken at specified intervals (commonly 30 and 60 minutes) to measure stimulated serum cortisol. The clinician interprets results in the context of baseline ACTH and clinical presentation to differentiate primary from secondary/tertiary adrenal insufficiency and to guide further management, which may include dynamic endocrine testing, imaging, or adjustment of glucocorticoid therapy. Typical sites of service include outpatient hospital outpatient departments, ambulatory infusion centers, endocrine clinic procedure rooms, and inpatient wards when assessing critically ill patients.

    Related CPT Codes

    CPT CodeDescriptionRelationship to This Procedure
    80053Comprehensive metabolic panelOften ordered with 80400 to assess electrolytes, glucose, and renal function when evaluating adrenal insufficiency.
    84436Assay of cortisolRoutine laboratory assay used for baseline and stimulated cortisol measurements obtained during the ACTH stimulation test.
    84402Assay of aldosteroneMay be ordered alongside cortisol to evaluate primary aldosteronism or mineralocorticoid axis involvement.
    82728Adrenocorticotropic hormone (ACTH) assayMeasurement of plasma ACTH helps distinguish primary from secondary adrenal insufficiency and is commonly ordered with 80400.
    96372Therapeutic, prophylactic, or diagnostic injection (subcutaneous or intramuscular)If cosyntropin is administered intramuscularly in an outpatient setting and the injection is billed separately, this code may be used in workflow.

    Related Modifiers

    8 rows

    ModifierDescriptionWhen to Use
    26Modifier 26 (Professional Component) identifies and bills only the professional portion of a split service — the physician’s interpretation, report, and medical judgment — when the technical…- Use CPT Modifier -26 when you are billing only the professional component (PC) of a split‑bill eligible service—i.e., you performed the physician interpretation, medical judgment and prepared a…
    59Modifier 59 indicates a distinct procedural service when two procedures that are not normally billed together are clinically and procedurally separate. The CPT definition (as reiterated by CMS)…- Use modifier -59 to report a distinct procedural service when documentation supports that the procedure reported is not normally billed together with another service on the same day because of a…
    91Modifier 91 — “Repeat Clinical Diagnostic Laboratory Test” — is appended when the exact same CPT laboratory test is performed more than once for the same patient on the same day because serial,…- Use modifier 91 when the exact same CPT laboratory test is performed more than once on the same patient on the same date because serial or repeated testing is medically necessary to monitor…
    52Modifier ‑52 (Reduced Services) indicates that a service or procedure was partially reduced or omitted at the provider’s discretion, allowing reporting of the basic procedure number with a qualifier…- Use modifier -52 when a physician or qualified health professional electively reduces or omits part of a procedure or service (for example, performing fewer required views or omitting a portion of…
    53Modifier 53 (Discontinued Procedure) signals that a surgical or diagnostic service was begun by the physician but terminated because of extenuating circumstances that threatened the patient’s…- Use modifier -53 when a physician/qualified healthcare professional has started a surgical or diagnostic procedure (e.g., anesthesia administered, incision or scope insertion) and then discontinues…
    76Modifier -76, Repeat Procedure or Service by Same Physician or Other Qualified Health Care Professional, is appended when the same provider performs an identical, medically necessary procedure or…- Use modifier -76 when the same physician or other qualified health care professional performs an identical procedure or service a second (or subsequent) time on the same date of service and the…
    77Modifier 77 indicates that a previously performed procedure or service was legitimately repeated by a different physician or other qualified health care professional. The AMA’s CPT definition…- Use modifier 77 when a basic procedure or service already performed is repeated by a different physician or other qualified health care professional (for example, a second provider independently…
    90Modifier ‑90 (Reference/Outside Laboratory) indicates that a laboratory test was performed by an entity other than the treating or reporting provider. The American Medical Association defines…- Use CPT modifier -90 when a laboratory test is performed by an outside/reference laboratory (an entity other than the treating or reporting physician or qualified professional) and the claim needs…

    Related Provider Taxonomies

    8 rows

    Taxonomy Code
    207K00000X
    207L00000X
    207RC0000X
    363L00000X
    2471C3402X
    2251P0200X
    2471Q0001X
    2086H0002X

    Related ICD-10-CM Codes

    29 rows

    ICD-10-CM CodeDescription
    E24.0Pituitary-dependent Cushing's disease
    E24.1Nelson's syndrome
    E24.2Drug-induced Cushing's syndrome
    E24.9Cushing's syndrome, unspecified
    E27.0Other adrenocortical overactivity
    E27.1Primary adrenocortical insufficiency
    E27.2Addisonian crisis
    E27.3Drug-induced adrenocortical insufficiency
    E27.8Other specified disorders of adrenal gland
    E27.9Disorder of adrenal gland, unspecified

    Showing 1–10 of 29

    Related Payer Policy Updates

    Specialty: Endocrinology1 / 3

    10 rows

    PolicyPayerEffective Date
    Diabetic SuppliesCigna2026-10-15
    Radiofrequency Ablation for Thyroid NodulesCigna2026-10-15
    Continuous Glucose Monitoring and Insulin Delivery for Managing Diabetes (for Idaho Only)UnitedHealthcare2026-10-01
    Tzield (teplizumab-mzwv) CoverageUnitedHealthcare2026-10-01
    Continuous Glucose Monitoring and Insulin Delivery for Managing Diabetes (for Indiana Only)UnitedHealthcare2026-10-01
    Medical Necessity Guidelines Insulin PumpsMass General Brigham Health Plan2026-10-01
    Medical Necessity Guidelines: Continuous Glucose MonitorsMass General Brigham Health Plan2026-10-01
    Continuous Glucose MonitoringAmbetter Nevada2026-10-01
    Salivary Hormone TestingOscar Health2026-10-01
    Bone Turnover Markers TestingOscar Health2026-10-01

    Related Codes

    CPT-80402-ACTH-STIMULATION-TEST-ADRENAL-FUNCTION

    CPT 80402: ACTH Stimulation Test for Adrenal Function

    CPT-80406-ACTH-STIMULATION-TEST-ADRENAL-FUNCTION

    CPT 80406: ACTH Stimulation Test for Adrenal Function

    CPT-80408-ALDOSTERONE-SUPPRESSION-EVALUATION-PANEL-SALINE-INFUSION

    CPT 80408: Aldosterone Suppression Evaluation Panel

    CPT-80410-CALCITONIN-STIMULATION-PANEL-THREE-TESTS

    CPT 80410: Calcitonin Stimulation Panel, Three Measurements

    CPT-80412-CRH-STIMULATION-PANEL-CORTISOL-ACTH-ASSAYS

    CPT 80412: CRH Stimulation Panel with Cortisol and ACTH Assays

    CPT-80414-CHORIONIC-GONADOTROPIN-STIMULATION-TEST-TESTOSTERONE-PANEL

    CPT 80414: Chorionic Gonadotropin Stimulation Panel for Testosterone Response

    CPT-80415-CHORIONIC-GONADOTROPIN-ESTRADIOL-STIMULATION-PANEL

    CPT 80415: Chorionic Gonadotropin Stimulation Estradiol Panel

    CPT-80416-RENAL-VEIN-RENIN-MEASUREMENT

    CPT 80416: Renal Vein Renin Measurement Pre- and Post-Stimulant

    CPT-80417-STIMULATED-RENIN-MEASUREMENT

    CPT 80417: Renin Measurement Before and After Captopril Stimulation

    CPT-80418-ANTERIOR-PITUITARY-EVALUATION-PANEL-RAPID

    CPT 80418: Rapid Anterior Pituitary Evaluation Panel

    Showing 1–10 of 22

    Frequently Asked Questions

    References

    1. 1.CPT® Codes and Descriptions. AAPC. Retrieved Aug 11, 2026.Maintains the CPT code set's official descriptions and guidelines, licensed from the American Medical Association, used as the definitional source for CPT codes on this page.
    2. 2.HCPCS Quarterly Update. Centers for Medicare & Medicaid Services (CMS). Retrieved Aug 11, 2026.CMS's quarterly release of HCPCS Level II codes and short/long descriptors, the source for HCPCS code definitions and update history.
    3. 3.ICD-10-CM Full Code List. Centers for Medicare & Medicaid Services (CMS). Retrieved Aug 11, 2026.CMS's complete ICD-10-CM diagnosis code list, used to cross-reference diagnosis codes associated with this procedure or service.
    Published by

    Trek Health powers OpenPayer with a leading commercial payer intelligence platform, seamlessly converting fragmented payer data into actionable insights for provider organizations.

    Trek Health ingests and normalizes Transparency in Coverage data and payer policy updates to give provider organizations a clear view of how commercial reimbursement behaves across markets, payers, and services. Our platform transforms raw payer disclosures into structured intelligence that supports contract evaluation, payer negotiations, and service line strategy. By combining market benchmarks with ongoing policy visibility, Trek helps teams identify variability, risk, and opportunity in commercial reimbursement. The result is faster insight, stronger negotiating positions, and more informed financial decisions.