Ordering Recommendation

New York DOH Approval Status

This test is New York state approved.

Specimen Required

Patient Preparation

Plasma Separator Tube (PST) or Serum Separator Tube (SST). Collect one tube per timed specimen. Also acceptable: Green (sodium or lithium heparin), Lavender (EDTA), or Pink (K2EDTA).

Specimen Preparation

Allow specimen to clot completely at room temperature. Separate from cells ASAP or within 2 hours of collection. Transfer 1 mL serum or plasma per timed specimen to individual ARUP Standard Transport Tubes. (Min: 0.4 mL per timed specimen)

Storage/Transport Temperature

Frozen. Also acceptable: Refrigerated.

Unacceptable Conditions

Tissue or urine. Grossly hemolyzed or lipemic specimens.


Ambient: 24 hours; Refrigerated: 1 week; Frozen: 2 months


Quantitative Chemiluminescent Immunoassay




1-2 days

Reference Interval

Interpretive Data

For pediatric patients, very low peak growth hormone (GH) concentrations on stimulation testing are consistent with severe GH deficiency (GHD). Thresholds distinguishing normal from partial GHD have not been well established. Inadequate response to two different provocative tests is required for diagnosis of GHD. (Grimberg et al. Horm Res Paediatr 2016;86:361-397).
In adults, expected peak GH concentrations depend on the stimulation test performed, as described in Endocrine Society guidelines for the evaluation and treatment of adults with GHD (Yuen KCJ et al. Endocr Pract. 2019;25(11):1191-1232).
For suppression testing, healthy subjects have GH concentrations of less than 1 ng/mL within 2 hours of ingestion of a 75 or 100 gram glucose dose. Patients with acromegaly fail to show normal suppression. (Katznelson et al. J Clin Endocrinol Metab, 2014, 99(11):3933-3951).

Compliance Category



This Growth Hormone assay is now standardized to the Recombinant Second International Standard (IS): 98/574. Growth hormone results read approximately 25 percent lower than with the previous standards (First IS: 80/505). Reference ranges have also been modified according to the assay manufacturer.

Hotline History


CPT Codes



Component Test Code* Component Chart Name LOINC
2013928 Growth Hormone 180 Minutes 56500-2
* Component test codes cannot be used to order tests. The information provided here is not sufficient for interface builds; for a complete test mix, please click the sidebar link to access the Interface Map.


  • GH
  • GH testing
  • GNRH
  • Growth Hormone Provocative Test
  • Growth Hormone Stimulation
  • growth hormone, Serum
  • hGH
  • Human Growth Hormone
  • Somatrophic Hormone
  • Somatrophin
Growth Hormone, 180 Minutes