Tesamorelin: GHRH Analog and Visceral Fat

What tesamorelin is

Tesamorelin is a stabilized synthetic analog of GHRH (growth-hormone-releasing hormone), the hypothalamic signal that normally tells the pituitary to release GH. A chemical modification at its terminus makes it more resistant to enzymatic degradation, so it acts longer than natural GHRH.

Marketed as Egrifta, it received FDA approval in 2010 with a specific indication: to reduce excess abdominal fat (visceral adipose tissue) in patients with HIV-associated lipodystrophy. It is therefore one of the few GH-axis analogs with human regulatory approval for a body-composition indication.

Mechanism: GHRH → GH → IGF-1 axis

Tesamorelin binds the GHRH receptor on somatotroph cells in the anterior pituitary. This triggers release of the body's own growth hormone in a pulsatile fashion — mimicking the physiological pattern rather than flooding the system with a flat, constant level.

The released GH acts on the liver and other tissues, where it stimulates production of IGF-1 (insulin-like growth factor 1), the mediator of many of GH's effects. The chain is easy to remember:

• GHRH (tesamorelin) → binds the pituitary GHRH receptor.
• GH → endogenous, pulsatile release from the body's own pituitary.
• IGF-1 → downstream mediator of the metabolic and tissue effects.

The key difference from injecting GH directly is that tesamorelin preserves the natural feedback loops: if IGF-1 levels rise too high, somatostatin can brake GH release. This reduces the risk of the sustained supraphysiological spikes seen with exogenous GH.

Visceral fat and NAFLD (the most studied)

The strongest body of evidence for tesamorelin is in visceral adipose tissue (VAT) — the deep fat surrounding the abdominal organs, which is associated with cardiometabolic risk. The trials that supported its approval showed consistent VAT reductions in patients with HIV-associated visceral fat accumulation.

An active research area is liver fat and non-alcoholic fatty liver disease (NAFLD/MASLD). Several studies have examined whether the GH and IGF-1 elevation induced by tesamorelin can reduce hepatic fat fraction and limit steatosis progression. The findings are promising but remain in the research domain.

More exploratory still, some studies have evaluated tesamorelin in the context of cognition in mild cognitive impairment, on the hypothesis that modulating the GH/IGF-1 axis might influence brain function. This line is preliminary and is not an established indication.

Tesamorelin vs exogenous GH vs secretagogues (CJC/Ipa)

Approach	How it acts	Feedback
Exogenous GH	Injects the hormone directly	Overrides natural regulation
Tesamorelin (GHRH)	Stimulates endogenous GH via GHRH receptor	Preserves the natural axis
CJC-1295 / Ipamorelin	GH-axis secretagogues (different class)	Preserves the natural axis

Tesamorelin is a GHRH analog: it mimics the original hypothalamic signal. Compounds like CJC-1295 and Ipamorelin also act on the GH axis to promote endogenous release, but they belong to a different class of secretagogues (CJC-1295 is itself a long-acting GHRH analog, while Ipamorelin is a ghrelin-receptor agonist/secretagogue). Exogenous GH, by contrast, stimulates nothing: it replaces the hormone, bypassing the body's own regulation. We go deeper into this pulse dynamic in our CJC-1295 + Ipamorelin guide.

Reconstitution

Tesamorelin is offered as a lyophilized powder in a 10 mg vial, reconstituted with bacteriostatic water at the concentration you define.

Calculation example (10 mg vial + 2 mL = 5 mg/mL): to research 1 mg → 0.2 mL → 20 units on a U100 syringe. If you reconstitute with 1 mL (10 mg/mL), that same 1 mg would be 0.1 mL → 10 units.

Refrigerate (2–8 °C) after reconstitution and protect from light. For custom calculations use the reconstitution calculator or see the complete reconstitution guide.

Tesamorelin at Renova

Tesamorelin is available as a lyophilized powder:

• 10 mg — $295 · lyophilized powder

Our material is manufactured in a cGMP-compliant US lab that we work with directly, with a Certificate of Analysis (COA) by HPLC and mass spectrometry.