← All Peptides & Hormones guides

Sermorelin Before-and-After Blood Work: What to Test

Sermorelin and similar growth-hormone secretagogue peptides are largely used off-label, and there is no single medical-society guideline covering their monitoring the way there is for TRT or GLP-1 therapy. This page covers the small set of markers with an established basis for monitoring growth-hormone-axis activity: what to test, not whether to start, how to dose, or where to source the peptide.

Medically reviewed · Guideline-anchored
Reviewed by Dr. Prahlad Rai Gupta, MBBS, MD · Thresholds anchored to published growth-hormone-axis monitoring literature · Evidence & Methodology
IGF-1 is the standard marker for GH-axis activity Baseline safety labs, not an efficacy claim What to test, not how to dose
Why do longevity researchers disagree on IGF-1?
Valter Longo targets a low IGF-1 for cancer-risk reduction; Peter Attia frames it as a balance against muscle loss. Neither position is about growth-hormone-secretagogue monitoring specifically.
See the optimal IGF-1 level guide

A narrower panel than TRT or GLP-1, because the guideline basis is narrower

Sermorelin stimulates the pituitary to release growth hormone, which the liver then converts into IGF-1. IGF-1 is the standard blood marker used to track that downstream effect, but the wider use case, off-label growth-hormone-secretagogue therapy for adults, does not have the same guideline-published monitoring schedule TRT and GLP-1 therapy have.

This page is part of FixFirst's Peptides & Hormones section. Sermorelin and related growth-hormone-releasing peptides are approved for specific pediatric growth-hormone-deficiency indications; use in adults for other purposes is off-label, meaning it falls outside an FDA-approved indication and outside the kind of society-published monitoring schedule that exists for TRT and GLP-1 therapy. This page states that plainly rather than implying a guideline framework that doesn't exist for this use case.

There is a further caveat for anyone who competes under anti-doping rules. Sermorelin and related growth-hormone-releasing peptides are on the World Anti-Doping Agency (WADA) Prohibited List (class S2, peptide hormones and growth factors), prohibited at all times, both in and out of competition. For any athlete subject to anti-doping testing, a growth-hormone secretagogue is not recommended or advised, independent of any monitoring question this page covers.

Growth hormone itself is difficult to measure reliably from a single blood draw because it releases from the pituitary in pulses rather than at a steady level. IGF-1, produced by the liver in response to growth hormone, stays comparatively stable across the day and is the standard proxy marker used instead. The optimal IGF-1 level guide in FixFirst's Longevity section covers how longevity researchers Valter Longo and Peter Attia frame IGF-1 differently, useful context for reading a result, though that page is about longevity-protocol framing, not sermorelin monitoring specifically.

This page does not make an efficacy claim about sermorelin, does not cover anti-aging outcomes, and does not cover dosing, cycling, or sourcing. Anyone using or considering a growth-hormone secretagogue should have that conversation, and this testing framework, with the physician overseeing it.

What to test

Two clusters: the GH-axis marker itself, and baseline safety labs relevant to elevated growth-hormone activity generally.

Cluster 1 of 2
Growth-hormone-axis activity
IGF-1 is the accepted proxy for growth hormone exposure over time, since growth hormone itself is hard to measure reliably from a single draw.
Core Usually in a standard panel Ask Request specifically
Core
IGF-1 (Insulin-like Growth Factor 1)
Reflects average growth hormone activity over roughly the prior 24 hours, more stable than a direct growth hormone measurement. A baseline value before starting, and a follow-up value, shows the direction and scale of change; reference ranges are age- and sex-adjusted and vary by lab assay.
Ask
IGFBP-3 (IGF Binding Protein 3)
The primary carrier protein for IGF-1 in circulation. Some labs and clinicians check it alongside IGF-1 for a fuller picture of GH-axis activity, since IGFBP-3 tends to be more stable and less affected by short-term factors like recent food intake.
Cluster 2 of 2
Baseline safety labs
Elevated growth-hormone activity affects glucose metabolism, so these are reasonable baseline and periodic checks independent of any specific product, before and during any therapy that raises growth hormone.
Core Usually in a standard panel Ask Request specifically
Core
Fasting Glucose
Growth hormone counteracts insulin, so a baseline fasting glucose is a reasonable safety check before starting a GH secretagogue, and periodically afterward, alongside HbA1c.
Ask
HbA1c
The 3-month rolling average, useful as a baseline and periodic check for the same reason as fasting glucose, since growth hormone's effect on insulin sensitivity is a mechanism worth tracking, not assuming.
Core
CBC & CMP (baseline safety panel)
A standard complete blood count and comprehensive metabolic panel, the general baseline bloodwork a prescribing physician would use to assess overall health and organ function before starting any new therapy, not specific to growth-hormone secretagogues.

Frequently asked questions

What blood tests should I get before starting sermorelin?
A baseline IGF-1, fasting glucose or HbA1c, and a general CBC/CMP safety panel are the markers with an established basis for monitoring GH-axis activity and metabolic effects. This is a testing checklist, not medical advice on whether to start a growth-hormone secretagogue, a decision to make with a physician given the largely off-label nature of this use.
Why test IGF-1 instead of growth hormone directly?
Growth hormone releases from the pituitary in short pulses rather than a steady level, so a single blood draw can catch a peak, a trough, or anything between, making it an unreliable single-draw marker. IGF-1, produced by the liver in response to growth hormone, stays comparatively stable across the day and reflects average GH activity over roughly the prior 24 hours.
Is sermorelin FDA-approved?
Sermorelin and related growth-hormone-releasing peptides have specific approved indications, historically including pediatric growth-hormone-deficiency evaluation. Use for other purposes in adults falls outside an FDA-approved indication, meaning it's off-label, without the same guideline-published monitoring schedule that exists for on-label therapies like TRT.
Is sermorelin banned in competitive sport?
Yes. Sermorelin and related growth-hormone-releasing peptides are on the World Anti-Doping Agency (WADA) Prohibited List (class S2, peptide hormones and growth factors), prohibited at all times, both in and out of competition. For any athlete subject to anti-doping testing, it is not recommended or advised.
Does sermorelin affect blood sugar?
Growth hormone counteracts insulin's effect on blood sugar, so it's a mechanism worth monitoring with a baseline and periodic fasting glucose or HbA1c, rather than assuming no effect. This page covers that as a testing consideration; it isn't a claim about how much any individual's blood sugar will change.

References & Guidelines

Keep reading: Peptides & Hormones section · Optimal IGF-1 level · Longevity blood markers hub

Once you have before-and-after results

Comparing two lab reports side by side is harder than it sounds when the layout or lab changes between draws. FixFirst reads both against the same clinical thresholds.

Upload to FixFirst
Get your top 3 priorities ranked in 45 seconds
Upload either report, or both, and FixFirst checks all 134 markers against standard clinical thresholds, adjusted for your sex and context.
Upload My Report →
More therapy-monitoring pages
See the full Peptides & Hormones section
TRT and GLP-1 before-and-after blood work, each built around what to test and when to retest.
Browse Peptides & Hormones
Free · No account · 45 seconds

Compare your before-and-after results against the same clinical thresholds.

Upload your blood report and get a ranked read on every marker, adjusted for your context.

Analyze My Blood Test →
Any lab PDF or phone photo · Processed in memory, never stored
Related guides
Peptides & Hormones sectionBefore-and-after blood work for TRT, GLP-1, and sermorelin, what to test and when to retest. Optimal IGF-1 levelValter Longo's lower-is-better case versus Peter Attia's balance framing, and where growth hormone peptides fit in. Longevity blood markers hubThe specific targets Peter Attia, Andrew Huberman, and other researchers cite in their own protocols. Optimal blood test ranges vs. normal"Normal" means inside 95% of a population, not ideal. What functional-medicine "optimal" ranges claim, attributed to their sources. GLP-1 Before-and-After Blood WorkGLP-1 receptor agonist medications (semaglutide, tirzepatide, and similar) primarily target blood sugar and appetite regulation, but the markers worth tracking extend beyond glucose. TRT Before-and-After Blood WorkTestosterone replacement therapy has a specific, guideline-published monitoring panel, not just a repeat testosterone level. Enter your blood test resultsUpload a PDF or photo, no account needed, and get your top 3 priorities in 45 seconds.