Item Value
Test name Growth Hormone Suppression Testing
Available Stat? No
Turn around times Glucose testing available 24 hours per day 7 days per week
Growth hormone: 1-8 days
In House Availability Glucose (GOTF, NP120): 24 hours per day 7 days per week
Growth Hormone: Sunday or Monday (day shift)
Performed by Fasting glucose (GOTF, NP120) Mission Bay, Mount Zion or Parnassus Chemistry
Growth hormone – China Basin Chemistry
Patient Preparation The patient should be instructed by the care-giver to eat a normal diet containing at least 150 g of carbohydrate and carry out normal physical activity for at least 3 days prior to the morning of the test. An 8-10 hour fast is required before initial baseline sample collection.
Normal range Growth hormone, baseline

Adult males < 3.1 µg/L
Adult females < 8.1 µg/L


Growth hormone 120 minute post glucose load: <0.4 µg/L

Note: some investigators consider growth hormone suppression test results that are < 0.4 micrograms/L (ng/mL) as normal whereas others consider results < 1.0 micrograms/L (ng/mL) as normal

GH reference range based on measurements in adults.

Growth hormone, baseline reference range was adopted from Siemens Immulite 2000 vendor performed studies and verified in-house by running adult donor samples (excluding autologous donors) on 20 male and 20 female samples.

Glucose reference ranges see lab manual entry for 2 Hour, 75 gram Glucose Tolerance Test, Non-pregnancy
Container type Gray top for fasting glucose (GOTF) and 120 min post glucose (NP120)
Gold top for growth hormone (GHB and GH120)
Amount to Collect 2 mL blood
Collection Instructions Outpatient testing at ACC available 0730-1400 weekdays, Mission Bay from 0700-1400 and at 2330 Post St. 0800-1400 weekdays.

The patient should be seated for the test and should not smoke.


For patients < 18 years of age, obtain the patient's weight and give the patient 1.75 g of glucose per kg of body weight. If the weight is in pounds, divide by 2.2 to get kg. Do not provide more than 75 g dose regardless of body weight.

If the fasting glucose is 125 mg/dL or higher, glucola will not be given and test will be aborted.
Sample type Plasma and Serum

If you have additional questions regarding this test, please call: 415-353-1667