Summary & Overview
CPT 80435: Insulin-Stimulated Glucose and Growth Hormone Testing
CPT code 80435 represents a dynamic laboratory test measuring glucose and human growth hormone (HGH) levels across five blood draws surrounding an insulin administration. This targeted endocrine diagnostic procedure assesses the physiologic responses to insulin and can inform evaluation of glucose regulation and growth hormone secretion abnormalities. The code matters nationally as hospitals, outpatient laboratories, and specialty endocrine centers bill for complex timed sampling protocols that require clinical coordination and laboratory analysis.
Key payers discussed include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find an explanation of the clinical context for CPT code 80435, typical sites of service, common billing considerations, and the payer landscape relevant to this type of endocrine diagnostic testing. The publication also outlines available benchmarks and policy considerations where provided and highlights procedural components that influence service lines and reimbursement pathways.
What readers will learn: the clinical intent and workflow for insulin-stimulated glucose and HGH sampling, payer coverage scope nationally for major commercial insurers and Medicare, and where to find additional details on coding, documentation, and billing components. Data not available in the input will be noted where applicable.
Billing Code Overview
CPT code 80435 describes a laboratory procedure in which a lab analyst measures glucose and human growth hormone (HGH) levels in five blood samples: one sample obtained before and four samples collected after the administration of insulin. The procedure evaluates biochemical responses to an insulin challenge to assess glucose regulation and growth hormone dynamics.
Service type: Diagnostic laboratory testing with dynamic insulin stimulation
Typical site of service: Hospital outpatient laboratory, clinical laboratory, or specialized endocrine testing facility
Clinical & Coding Specifications
Clinical Context
A 35-year-old adult is referred to an outpatient endocrinology clinic for evaluation of suspected insulinoma after reporting episodic fasting hypoglycemia, neuroglycopenic symptoms (confusion, sweating, tremor), and documented low capillary glucose values. The clinician schedules an insulin tolerance test where insulin is administered intravenously and five timed blood samples are collected: one baseline (pre-insulin) and four post-insulin draws to measure serum glucose and human growth hormone (GH) levels.
Pre-procedure, the patient is instructed to fast overnight and to withhold medications that affect glucose metabolism as appropriate. Vital signs and baseline labs are obtained, and intravenous access is placed in a monitored setting (clinic procedure room, ambulatory infusion center, or hospital outpatient department). Insulin is administered under physician supervision with cardiac and neurologic monitoring because hypoglycemia is induced. Blood specimens are processed by the clinical laboratory for quantitative glucose and GH assays. Results assist in diagnosing insulin-mediated hypoglycemia, growth hormone reserve or hypopituitarism, and in differentiating insulinoma from other causes of hypoglycemia.
Coding Specifications
| Modifier | Description | When to Use |
|---|---|---|
26 | Professional component | Use when only the physician interpretation is billed separately and the laboratory bills the technical component. |