Tesamorelin is a synthetic analog of growth-hormone-releasing hormone (GHRH) that stimulates the pituitary to release endogenous growth hormone in pulses. It is FDA-approved as Egrifta for HIV-related lipodystrophy. In research it is most-studied for visceral-adipose-tissue reduction and downstream IGF-1 effects.
Research notes
How does Tesamorelin work?
Tesamorelin is a synthetic analog of growth hormone-releasing hormone (GHRH) stabilized against rapid enzymatic degradation. Unlike direct exogenous growth hormone, tesamorelin works upstream — it stimulates the pituitary to release GH in the body's natural pulsatile pattern, which preserves the negative-feedback loops that regulate the GH–IGF-1 axis.
This mechanism distinguishes tesamorelin from related GH-axis compounds. Direct exogenous human growth hormone (hGH) bypasses the pituitary entirely; ghrelin-receptor agonists (ipamorelin, MK-677) act on a different receptor family. Tesamorelin specifically activates GHRH receptors.
The compound is FDA-approved as Egrifta for HIV-associated lipodystrophy (visceral fat reduction). Research-protocol use outside that indication is what most vendor catalog listings target.
What doses are used in research?
The approved Egrifta dose is 2 mg daily subcutaneous, administered before bed to align with the natural overnight GH pulse. Research-protocol literature follows the same schedule:
- 1 mg daily as a lower-end protocol dose
- 2 mg daily matching the FDA-approved schedule
- Cycling is common — 12-week on / 4-week off cycles appear in research-protocol writeups
Half-life is short (~30 minutes), which is why the timing of administration matters. The pituitary response continues for several hours after the peptide itself has been cleared.
What are the known side-effect concerns?
Reported side effects from clinical and research-protocol literature cluster in three categories:
- Injection-site reactions — most-reported; generally mild
- Joint stiffness / mild edema — class effect of GH-axis compounds; typically resolves with cycling
- Glucose tolerance changes — modest; monitored in clinical trials
What does this guide cover?
Vendor audits for tesamorelin focus on identity confirmation and purity at scale. The compound is structurally complex (44 amino acids), and lower-quality synthesis routes produce truncated peptide fragments that show up on HPLC as secondary peaks. We weight the per-batch HPLC chromatogram heavily for tesamorelin specifically.
What it's researched for
- visceral fat reduction
- GHRH analog research
- HIV-associated lipodystrophy (FDA-approved indication)
Where to source it
ALL 6 VENDORS →RANKED BY COMPOSITE SCORE · PRICES ARE SNAPSHOTS FROM THE PRICE INDEX · PER-MG IS A WITHIN-COMPOUND COMPARATOR
Frequently asked about Tesamorelin
What is tesamorelin?
Tesamorelin is a synthetic 44-amino-acid analog of growth-hormone-releasing hormone (GHRH). It binds the GHRH receptor on pituitary somatotrophs and stimulates pulsatile release of endogenous growth hormone, rather than introducing exogenous HGH directly.
How is tesamorelin different from HGH?
HGH is exogenous growth hormone administered directly; tesamorelin stimulates the body to release its own HGH in physiologic pulses. The pulsatile pattern is closer to natural GHRH signaling than continuous HGH administration, which may reduce some side effects associated with sustained HGH levels.
Is tesamorelin FDA-approved?
Yes — tesamorelin is FDA-approved as Egrifta for the reduction of excess abdominal fat in HIV-infected patients with lipodystrophy. It is not approved for general weight loss, anti-aging, or athletic-performance indications. Research-grade tesamorelin sold by peptide vendors is the same molecule but is not pharmaceutical-grade.
What doses are used in tesamorelin research?
The FDA-approved protocol for HIV-lipodystrophy is 2 mg subcutaneous daily. Research-grade material is typically reconstituted and dosed in the same range. Half-life is approximately 7 minutes systemically, but the downstream HGH pulse is the operative mechanism.
What is the typical purity of research-grade tesamorelin?
Janoshik Analytical tests in our corpus typically show 95–99% purity by HPLC for tesamorelin from audited vendors. Identity confirmation rates are usually high since the molecule has a distinctive mass signature. Per-vendor purity is in the leaderboard on this page.