These three get listed together on clinic menus as though they were three strengths of the same thing. They are not. Two of them are analogs of growth hormone-releasing hormone and one works on a different receptor entirely, and the regulator has reached a different conclusion about each of the three.
Those conclusions are the most useful way to rank them, because they are the one comparison that does not depend on whose marketing you read. One is approved and on the market today. One was approved twice and withdrawn. One was formally evaluated and turned down.
At a glance
| Tesamorelin | Sermorelin | Ipamorelin | |
|---|---|---|---|
| Receptor | GHRH receptor | GHRH receptor | Not GHRH — a ghrelin agonist and somatostatin inhibitor [1] |
| FDA verdict | Approved November 10, 2010 and marketed today [2] | Approved 1990 and 1997, both discontinued for commercial reasons [3] | Evaluated for the compounding bulks list in 2024 and recommended against [1] |
| Approved for what | Reduction of excess abdominal fat in HIV-infected adults with lipodystrophy — and nothing else [4] | Short stature in a narrow group of children with growth hormone deficiency [1] | Nothing, anywhere |
| Has a label you can read | Yes, with warnings on neoplasms, fluid retention and glucose [4] | Only a historical one; no current product | No |
| How you would get it | A finished, FDA-reviewed product, on prescription | Compounded to order | Compounded to order |
Tesamorelin: approved, and narrower than it sounds
Tesamorelin is the only one of the three you can get as a finished product. It was approved on November 10, 2010 as a new molecular entity and is still marketed [2]. That is a real distinction and it is worth understanding exactly what it covers.
The label indicates it for one thing: reducing excess abdominal fat in HIV-infected adults with lipodystrophy. It then adds a limitation that matters to anyone considering it for body composition generally — it “is not indicated for weight loss management as it has a weight neutral effect” — and notes that long-term cardiovascular safety has not been established [4]. An approval is a permission for a specific use in a specific population, not a general endorsement, and the pairwise comparison with sermorelin goes through the trial evidence behind it.
Sermorelin: approved, then taken off the market
Sermorelin is the middle case, and it is a genuinely odd one. It was approved twice, in 1990 and again in 1997, and both product records are now discontinued — each one carrying the FDA’s own Federal Register determination that it was not withdrawn for safety or effectiveness reasons [3]. A drug can leave the market because nobody was buying it.
What that leaves is a compound with a regulatory history and no current product, which is why every sermorelin sold in the United States is compounded, and why the approval question has a longer answer than yes or no. It also means the adult evidence is thin: one placebo-controlled trial in nineteen people [5].
Ipamorelin: evaluated, and recommended against
Ipamorelin is the one usually described as the newest and cleanest of the three. In October 2024 the FDA brought it to its Pharmacy Compounding Advisory Committee to decide whether it should be allowed as a bulk ingredient for compounding at all. The conclusion was that “a balancing of the criteria weighs against” placing either ipamorelin or ipamorelin acetate on that list [1].
The reasoning is more pointed than a simple lack of evidence. FDA found the substance “not well-characterized from the physical and chemical characterization perspective,” noted that the nomination packages “lacked CoAs” — certificates of analysis, the documents that establish identity and purity — and observed that because of its limited water solubility, “it is unclear how it would be possible to formulate the proposed injectable dosage form with the concentration of 2 mg/mL” [1].
That last sentence is a different order of finding. It is not the regulator saying a drug is unproven; it is the regulator saying it cannot see how the product being proposed would physically work at the stated concentration. If you are weighing ipamorelin, that belongs in the calculation alongside the mechanism difference and its trial record, and it is a strong argument for asking any seller for a certificate of analysis before ordering anything.
Two of these are the same kind of drug. One is not
Sermorelin and tesamorelin both act on the GHRH receptor, which is why both preserve the pituitary’s own rhythm rather than overriding it. Ipamorelin does not: the FDA’s own document describes it as a ghrelin agonist and somatostatin inhibitor [1], a separate pathway that converges on the same pituitary from a different direction.
This is why listing the three as a ladder of potency is a category error, and why the stacking pitch — combining a GHRH analog with ipamorelin for a larger release — has a mechanistic logic even though no trial has tested the combination in people.
The line on the approved label worth reading twice
Tesamorelin’s label is the only one of the three that exists, and it contains an instruction that reframes how the other two are sold. Under warnings: the drug “stimulates GH production and increases serum IGF-1, a growth factor. The effects of prolonged elevations in IGF-1 levels are unknown. Monitor IGF-1 levels during EGRIFTA SV therapy. Consider discontinuing in patients with persistent elevations” [4].
A sustained IGF-1 rise is, on the only FDA-reviewed label in this class, a reason to consider stopping. In the compounded peptide market the same rise is sold as confirmation the treatment is working. Both statements describe the same lab result. Only one of them was written by someone required to say what the risks are, and what an IGF-1 number actually tells you is the question underneath all three of these drugs.
How to choose between them
If you have HIV-associated lipodystrophy, tesamorelin is a licensed treatment for it and the conversation is with a physician about a finished product. If you do not, its approval does not transfer to you, and its own label says it is not a weight-loss drug.
Between sermorelin and ipamorelin, the regulatory record separates them more clearly than the marketing does. Sermorelin has a discontinued approval, a published adult trial and a characterized molecule. Ipamorelin has none of those, and has a 2024 FDA evaluation recommending against its use as a compounding ingredient. Neither is a settled treatment, and the questions worth putting to a prescriber apply to all three.