Growth Hormone (GH) blood Biomarker Testing
A GH test measures growth hormone in your blood to help evaluate pituitary function, with convenient ordering and Quest-based labs via Vitals Vault.
With Vitals Vault, you have access to a comprehensive range of biomarker tests.
Growth hormone (GH) is a pituitary hormone that helps regulate body composition, muscle and bone maintenance, and how your body uses fat and sugar. In children it supports linear growth, but in adults it is more about metabolism and tissue repair.
A GH blood test measures the amount of growth hormone circulating in your blood at the moment your sample is drawn. Because GH is released in pulses, a single number can be tricky to interpret on its own, so the most useful next step is often pairing it with related testing (especially IGF-1) or repeating it under the right conditions.
If you are reviewing a result, the goal is not to “chase a perfect GH number.” The goal is to understand whether your pituitary signaling looks appropriate for your age, symptoms, and the time and context of the blood draw.
Do I need a Growth Hormone (GH) test?
You might consider a GH test if you have symptoms or a history that raises questions about pituitary function. In adults, this can include unexplained changes in body composition (more fat, less muscle), low energy that does not match your sleep and training, reduced exercise capacity, or a history of pituitary surgery, head trauma, radiation, or known pituitary tumors.
A GH test can also be part of an evaluation for possible growth hormone excess. Clues can include increasing shoe or ring size, changes in facial features over time, new or worsening sleep apnea, headaches, sweating, joint pain, or carpal tunnel symptoms. These symptoms have many causes, but GH/IGF-1 testing helps clarify whether pituitary overproduction is on the list.
In children and adolescents, GH testing is usually ordered when growth pattern concerns show up on a growth chart, or when puberty timing and growth velocity do not fit the expected pattern.
Testing supports clinician-directed care because GH results often need confirmation with repeat testing or stimulation/suppression tests. You should not use a single GH value to self-diagnose or self-treat.
This is a CLIA-certified laboratory blood test; results are educational and should be interpreted with your clinician, especially because GH is pulsatile and method-dependent.
Lab testing
Order a Growth Hormone (GH) test and track your results over time
Schedule online, results typically within about a week
Clear reporting and optional clinician context
HSA/FSA eligible where applicable
Get this test with Vitals Vault
Vitals Vault lets you order a Growth Hormone (GH) blood test without needing to schedule a separate doctor visit just to obtain a lab order. You choose a convenient lab location, complete the draw, and then review your results in a clear, organized format.
Because GH can be hard to interpret in isolation, PocketMD can help you understand what your number may mean in context, what follow-up tests are commonly paired with GH (such as IGF-1), and when it makes sense to repeat testing under more controlled conditions.
If your result is unexpected, you can use the same workflow to recheck the marker or add companion labs so you and your clinician can make decisions based on a pattern rather than a one-off value.
- Order online and test at a nationwide Quest-based lab network
- Clear result tracking so you can compare trends over time
- PocketMD guidance to prepare questions for your clinician
Key benefits of Growth Hormone (GH) testing
- Adds a data point about pituitary hormone output when symptoms suggest an endocrine cause.
- Helps flag patterns consistent with GH excess when paired with IGF-1 and clinical findings.
- Supports evaluation of possible GH deficiency in higher-risk situations (pituitary disease, surgery, radiation, head trauma).
- Provides a baseline before and during clinician-supervised therapy that may affect the GH/IGF-1 axis.
- Helps you decide whether a one-time result needs repeat testing due to GH’s normal pulsatile release.
- Guides smarter follow-up testing (IGF-1, glucose, thyroid, cortisol, prolactin) instead of guessing.
- Makes it easier to track results over time and discuss next steps using PocketMD and your clinician.
What is Growth Hormone (GH)?
Growth hormone (GH), also called somatotropin, is made by your pituitary gland, a small gland at the base of your brain. GH is released in bursts throughout the day, with larger pulses often occurring during sleep. Because of this pulsed pattern, your blood level can be low at one moment and higher at another even when your overall GH production is normal.
GH acts directly on tissues and also signals your liver and other tissues to produce insulin-like growth factor 1 (IGF-1). IGF-1 is more stable throughout the day, which is why many clinicians use IGF-1 as the primary screening test for chronic GH excess or deficiency, and then use GH testing (including dynamic testing) to confirm.
In adults, GH influences body composition, lipid metabolism, and tissue repair. In children, GH is essential for normal growth and development, but interpretation and follow-up are typically handled by pediatric endocrinology.
GH vs. IGF-1: why both may matter
A random GH level is a snapshot, while IGF-1 reflects average GH signaling over time. If your GH is “normal” but IGF-1 is high, that can still suggest excess GH activity. If your GH is low but IGF-1 is normal and you are not in a high-risk group, the low GH may simply reflect timing of the pulse rather than a true deficiency.
How GH is usually evaluated clinically
When clinicians suspect GH deficiency or excess, they often start with IGF-1 and clinical history. If the picture remains unclear, they may use stimulation tests (to see if GH can rise appropriately) or suppression tests (to see if GH can be turned down appropriately), because these approaches reduce the noise created by normal pulses.
What do my Growth Hormone (GH) results mean?
Low GH levels
A low GH result is common on a random blood draw because GH is released in bursts, and between pulses the level can be very low. If you are not in a high-risk group, a single low value often does not prove deficiency. Low GH becomes more meaningful when it matches symptoms and risk factors (such as known pituitary disease) and when IGF-1 is also low or when a stimulation test shows an inadequate rise.
In-range (expected) GH levels
An in-range GH result means your measured value fits the lab’s reference interval for that assay, but it still reflects only one moment in time. If your symptoms strongly suggest a pituitary issue, your clinician may still look at IGF-1, other pituitary hormones, and sometimes imaging. For many people, an in-range result is reassuring when it aligns with a normal IGF-1 and no high-risk history.
High GH levels
A high GH value can occur during a normal pulse, after exercise, during stress, or with low blood sugar, so it is not automatically abnormal. Persistently elevated GH signaling is more often assessed with IGF-1, and if IGF-1 is high, clinicians may use a glucose suppression test to see whether GH appropriately decreases. If you have symptoms suggestive of GH excess, a high GH result is a reason to follow up rather than a diagnosis by itself.
Factors that influence GH results
Timing matters because GH pulses, and levels can rise during sleep, exercise, acute illness, pain, and psychological stress. Blood sugar also affects GH, since hypoglycemia can stimulate GH release, while high glucose can suppress it. Age, body composition, and certain medications can shift GH/IGF-1 signaling, and different lab methods can produce different numeric ranges. If you are retesting, try to keep conditions similar (time of day, fasting status if instructed, and avoiding intense exercise beforehand).
What’s included
- Growth Hormone (Gh)
Frequently Asked Questions
Is a random growth hormone (GH) blood test reliable?
It can be useful, but it is limited because GH is released in pulses. A single random value may be low between pulses or high during a normal pulse. That is why clinicians often pair GH with IGF-1 or use stimulation/suppression testing when they need a clearer answer.
Do I need to fast for a GH test?
Fasting requirements can vary by clinician and lab protocol, and GH can be influenced by blood sugar. If you are testing to compare results over time, it helps to keep conditions consistent and avoid heavy exercise beforehand. Follow the instructions provided with your order, and ask your clinician if you are also checking glucose or insulin-related markers.
What is the difference between GH and IGF-1 testing?
GH is a moment-in-time measurement that changes throughout the day, while IGF-1 is more stable and reflects average GH signaling. IGF-1 is commonly used to screen for chronic GH excess (such as acromegaly) or deficiency, and GH testing is often used as a supporting or confirmatory piece of the evaluation.
What causes high GH levels on a blood test?
High GH can happen during normal physiology, including sleep-related pulses, recent exercise, stress, or low blood sugar. Persistently high GH activity is more concerning and is usually evaluated with IGF-1 and, when indicated, a glucose suppression test. Your clinician will interpret the result alongside symptoms and repeat testing when needed.
What causes low GH levels in adults?
A low random GH level is often just timing between pulses. True GH deficiency in adults is more likely when there is pituitary disease or damage (tumors, surgery, radiation, significant head trauma) and when IGF-1 is low or stimulation testing shows an inadequate GH rise. Other hormone issues (thyroid, cortisol, sex hormones) can also affect how you feel, so broader pituitary evaluation is common.
When should I retest GH?
Retesting depends on why you tested in the first place. If the result does not match your symptoms or risk factors, your clinician may recommend repeating it under more controlled conditions, adding IGF-1, or moving to dynamic testing rather than repeating random GH levels. If you are monitoring treatment that affects the GH/IGF-1 axis, your clinician will set the timing based on the therapy and goals.
Can supplements or lifestyle changes meaningfully change GH lab results?
Sleep, exercise, and calorie balance can influence GH pulses, and acute factors like intense workouts can raise GH temporarily. However, changing a single lab value is not the goal; the goal is understanding whether your overall GH/IGF-1 signaling is appropriate for your situation. If you are making lifestyle changes, consistent retesting conditions help you avoid confusing short-term spikes with meaningful trends.