Sermorelin
The first 29 amino acids of GHRH. Was FDA-approved as Geref for pediatric growth hormone deficiency until 2008. Every dose today is compounded.
Tesamorelin
A stabilised GHRH analog, FDA-approved as Egrifta since 2010 for visceral fat in HIV-associated lipodystrophy. The only GH peptide with imaging-based outcome trials.
Side-by-Side Comparison
Approved as Geref in 1990 for diagnostic use and 1997 for pediatric growth hormone deficiency. Discontinued by the manufacturer in 2008 for commercial reasons; the FDA later formally confirmed it was not withdrawn for safety or effectiveness.
Approved as Egrifta since 2010 for reducing excess abdominal fat in people with HIV-associated lipodystrophy. A live approval with a labelled dose and manufacturing oversight.
Cleared the FDA approval bar in 1997, which requires adequate and well-controlled trials. Those trials predate modern reporting standards and are not readily available for re-analysis.
Reduced visceral fat by 15.2% over 26 weeks versus a 5.0% increase on placebo, measured by imaging rather than self-report. Replicated in a second 26-week trial.
We could not identify randomized trials testing sermorelin for body composition, energy, sleep, or aging markers in healthy adults. The case is an extrapolation from growth hormone physiology.
The pivotal trials enrolled people whose visceral fat came from antiretroviral therapy, a different underlying cause from ordinary age-related belly fat. A separate 152-person randomized trial also found improved executive function over 20 weeks.
No published imaging study of body composition in adults.
Selectively reduces the deep fat around your organs while largely sparing the subcutaneous layer you can pinch. Your waist measurement may drop without a dramatic visible change.
Half-life of roughly 10 to 20 minutes, so it needs nightly dosing at bedtime to align with the natural GH pulse.
Approved dose is 2mg subcutaneously once daily. Supplied as a powder requiring reconstitution.
Widely dispensed by compounding pharmacies. Potency and purity depend entirely on the pharmacy, since there is no approved finished product.
A branded specialty drug. Cost is the main practical barrier for anyone using it off-label, and insurance is unlikely to cover non-HIV use.
Fluid retention, joint aches, and reduced insulin sensitivity at higher doses. The short half-life means effects clear quickly if you stop.
Same growth hormone effects, plus a documented reduction in insulin sensitivity that warrants fasting glucose and HbA1c monitoring. Visceral fat returns after stopping.
Both are GHRH analogs doing the same basic job: signalling your pituitary to release growth hormone in natural pulses, rather than injecting synthetic growth hormone and overriding the feedback loop. On mechanism they are close cousins.
On evidence they are not close at all.
**Tesamorelin** has a live FDA approval, a labelled dose, manufacturing oversight, and a 412-person NEJM trial with an imaging-based endpoint showing a 15.2% reduction in visceral fat. It also has the single most interesting result in this entire category: a separate 152-person randomized controlled trial found improved executive function in older adults. That is a real trial measuring a real outcome, which almost nothing else in the peptide world can claim.
**Sermorelin** has a genuine approval history, which is more than most peptides, but that approval was for growth hormone deficiency in children. We could not find randomized trials testing it for the adult body composition and anti-aging uses it is overwhelmingly prescribed for today.
So if evidence quality is your deciding factor, this is not a close call. The honest counterweight is cost: tesamorelin is an expensive specialty drug and sermorelin is cheap and easy to get, which is a large part of why sermorelin is what most clinics actually dispense.
Which Is Right for You?
- Cost is the deciding constraint
- You want something with an FDA approval history and a USP monograph behind the ingredient
- You accept that the adult wellness use is an extrapolation, not an evidence-based indication
- You want a short half-life so effects clear quickly if something goes wrong
- You want the GH peptide with actual outcome trials behind it
- Visceral fat specifically is the target
- You have HIV-associated lipodystrophy, the approved indication
- The cognition finding interests you and you understand it is one unreplicated trial
- You can absorb the cost of a branded specialty drug
Important Note
This comparison is for educational purposes only and should not replace medical advice. The best medication for you depends on your individual health profile, medical history, and personal circumstances. Always consult with a healthcare provider who can evaluate your specific situation before starting any medication.
Frequently Asked Questions
Is tesamorelin better than sermorelin?
On evidence, clearly. Tesamorelin has a live FDA approval and a 412-person NEJM trial showing a 15.2% reduction in visceral fat measured by imaging, plus a separate randomized trial finding improved executive function in older adults. Sermorelin has an approval history, but it was for growth hormone deficiency in children, and we could not identify randomized trials for the adult uses it is now prescribed for. On cost and availability, sermorelin wins easily.
Why is sermorelin no longer FDA-approved?
Commercial reasons, not safety. EMD Serono discontinued Geref in 2008 and asked the FDA to withdraw the approvals, because recombinant human growth hormone had taken over the pediatric market and Geref was no longer worth manufacturing. The FDA published a determination in 2013 confirming it was not withdrawn for reasons of safety or effectiveness.
Does either one help with anti-aging?
Neither has been tested for that. Tesamorelin comes closest, with a randomized trial showing improved executive function in older adults over 20 weeks, but that is a single unreplicated trial with modest effect sizes. Sermorelin has no published trials in healthy adults at all. Both raise IGF-1, which is measurable, but a hormone level going up is not the same as a health benefit.
Will tesamorelin reduce my belly fat?
It reduces visceral fat, the deep fat around your organs, by about 15% in the population studied. It does not meaningfully reduce subcutaneous fat, the layer you can pinch, so your waist measurement may drop without a dramatic change in how your stomach looks. Visceral fat is the more metabolically harmful kind, so this is arguably the better target, just not the one people expect.
Do I have to inject these every day?
Yes, both. Sermorelin has a half-life of roughly 10 to 20 minutes and is dosed nightly at bedtime to match the natural growth hormone pulse. Tesamorelin is approved at 2mg subcutaneously once daily. If daily injections are the obstacle, CJC-1295 with DAC lasts about a week, though it has no FDA approval and only a single published human pharmacology study.