Ipamorelin vs Tesamorelin
Sold for anti-aging, fat loss and muscle. It does raise growth hormone in people, but the one outcome trial, in 117 bowel surgery patients, did not work. It is a shot that cuts belly fat in people with HIV. It cut deep belly fat about 15% in six months, but the fat returned after stopping, and outside HIV there is one trial of 60 people.
Tesamorelin has the stronger evidence, grade B (some human evidence) against grade C for Ipamorelin. Ipamorelin: Not approved. Tesamorelin: FDA approved.
Evidence
CAnimal and cell studies
BSome human evidence
Human studies cited
Animal or cell studies cited
Why the grade
For the anti-aging and body-composition use ipamorelin is sold for, no human trial exists. The human data are a 40-volunteer dose-escalation pharmacokinetic study showing a single growth hormone pulse, a 114-patient randomised phase 2 trial in post-operative ileus that found no benefit, and a comparative hormone study of related peptides. The selectivity claim comes from rats and swine.
Two phase 3 randomized trials in HIV-associated abdominal fat, pooled at 806 patients, support the approved indication, which would be A for that use. The use tesamorelin is best known for outside clinics, trimming visceral fat in people without HIV, rests on one 60-person randomized trial in obese adults with reduced growth hormone and one 61-person trial in HIV-related fatty liver, so the popular use grades B.
FDA
Not approved
Ipamorelin is not approved by the FDA for any use and is sold online as a research chemical; its development for post-operative ileus was abandoned after a negative phase 2 trial. In 2023 the FDA placed it in Category 2 of its compounding lists, the category for substances with significant safety risks, and it remains there for outsourcing facilities (503B) although the nominations for pharmacy compounding (503A) were withdrawn in 2024. In October 2024 the Pharmacy Compounding Advisory Committee voted 12 to 0, with one abstention, against adding it to the 503A bulks list.
FDA approved
Tesamorelin is approved by the FDA as Egrifta (2010), Egrifta SV, and Egrifta WR (2025) to reduce excess abdominal fat in adults with HIV and lipodystrophy. It is not approved for weight loss, fat loss in people without HIV, or anti-aging.
Sold for
Ipamorelin is sold as the cleanest growth hormone secretagogue, for anti-aging, fat loss and muscle, usually paired with CJC-1295.
Tesamorelin is marketed by longevity and body-composition clinics as a growth-hormone-releasing injection that melts belly fat without the risks of growth hormone itself.
Studies say
Ipamorelin releases growth hormone in humans without the cortisol rise seen with GHRP-2 and GHRP-6, but the only outcome trial, in bowel surgery patients, was negative, and no study has measured body composition or aging, so the grade is C.
In people with HIV it reliably cuts visceral fat by about 15 percent over six months, but the fat returns when the drug stops and the evidence in people without HIV is a single small trial, which is the logic of the B grade.
Class
GHRP / ghrelin receptor agonist
GHRH analog
Route
Injection
Injection