Sermorelin vs Tesamorelin
An evidence-first, side-by-side comparison. We compare what the research supports — not marketing claims.
Last updated
Evidence grade
Human (observational)
Human RCT
What that means
Human data from non-randomized studies: cohorts, case series, case reports.
Randomized controlled trials in humans — the strongest evidence we grade.
Status
Prescription
FDA-approved
Mechanism
Sermorelin is the acetate salt of GHRH(1-29)NH2, the active N-terminal piece of the body's own growth hormone-releasing hormone. It binds pituitary GHRH receptors and triggers physiological, pulsatile GH release, keeping the normal GH–somatostatin–IGF-1 feedback loop intact in a way that straight GH replacement does not. The trade-off is duration: its half-life runs in minutes, not the hours of tesamorelin or CJC-1295, so it needs frequent dosing to keep the pituitary engaged. And it cannot push GH past what the gland is willing to make — a safety feature and a hard ceiling on effect, at the same time.
Tesamorelin is a synthetic GHRH analog, stabilized with a trans-3-hexenoic acid group that lets it outlast the body's own GHRH(1-44). It binds pituitary GHRH receptors and prompts the gland to release its own GH in pulses, which then lifts IGF-1. The point worth holding onto: it works through the natural pituitary–GH–IGF-1 axis rather than overriding it. The downstream result that earned approval is a measurable drop in visceral fat, studied most thoroughly in HIV-associated lipodystrophy.
Goals
GH / IGF-1 support, Body composition, Sleep & recovery
Visceral fat reduction, Body composition, GH / IGF-1 support
Key risks
- Evidence base in adults is observational and review-level — no modern large RCTs
- Compounding pharmacy products vary in purity and sterility standards
- Injection-site reactions; flushing; headache reported
- FDA approval is narrow: HIV-associated lipodystrophy only — use in other populations is off-label and evidence-free
- Can cause fluid retention, arthralgia, myalgia, and peripheral edema
- Raises IGF-1; potential concern in individuals with active malignancy (not studied in cancer patients)
Regulatory
Available in the US only via prescription or a compounding pharmacy.
Approved by the FDA for one or more human indications.