Ipamorelin vs Tesamorelin
Growth Hormone
Ipamorelin
Highly selective pentapeptide ghrelin receptor agonist, notable for minimal cross-activation of other pituitary axes.
Growth Hormone
Tesamorelin
Stabilized 44-amino-acid GHRH analog — the longest GHRH sequence in common research use.
Side by side
| Dimension | Ipamorelin | Tesamorelin |
|---|---|---|
| Molecular weight A 7.2× difference in mass — these are not comparable on a milligram-for-milligram basis. | 711.85 g/mol | 5135.86 g/mol |
| Size class | short peptide | long peptide |
| CAS number | 170851-70-4 | 218949-48-5 |
| Research area | growth hormone | growth hormone |
| Sequence | Aib-His-D-2-Nal-D-Phe-Lys-NH2 | Not published as a linear sequence |
| Available sizes | 5mg, 10mg | 10mg, 15mg |
| Entry price | $39 | $64 |
| Cost per mg | $4.90 | $5.93 |
Mechanism
Ipamorelin
Ipamorelin is a synthetic pentapeptide agonist at the growth hormone secretagogue receptor (GHS-R1a). Its defining research characteristic is selectivity: unlike earlier secretagogues such as GHRP-6 and GHRP-2, it shows minimal effect on ACTH, cortisol, and prolactin at comparable doses in animal models. That clean profile is precisely why it remains a useful tool compound for isolating GH-axis effects.
Tesamorelin
Tesamorelin is a synthetic analog of full-length human GHRH(1-44) with a trans-3-hexenoyl group attached at the N-terminus, conferring resistance to DPP-4 cleavage. It is distinguished from sermorelin and Modified GRF (1-29) by sequence length: those are truncated to the first 29 residues, whereas tesamorelin retains the complete 44-residue sequence. It has an established clinical literature, which is uncommon in this catalog.
Evidence quality
Mechanism is not the same as evidence. Where we have assessed the literature, the verdict is stated plainly.
Ipamorelin
Evidence base: small but well-defined. The selectivity result is clearly established and the receptor pharmacology is characterised. Primary evidence is concentrated in four papers from 1998 and 1999, with little added since.
Full research reference →Tesamorelin
Evidence base: strong for the approved indication, supported by pooled phase 3 data with safety extension. Evidence outside that population and endpoint is limited, and the recent neurocognitive work is single-study.
Full research reference →Research applications
Ipamorelin
- GHS-R1a receptor selectivity and binding studies
- Pituitary somatotroph response assays
- Comparative secretagogue selectivity profiling
- Pulsatile secretion pattern research
Tesamorelin
- GHRH receptor binding and activation studies
- Comparative studies against truncated GHRH analogs
- Visceral adipose tissue metabolism research
- IGF-1 axis response profiling
Common questions
What is the difference between Ipamorelin and Tesamorelin?
Ipamorelin is highly selective pentapeptide ghrelin receptor agonist, notable for minimal cross-activation of other pituitary axes. Tesamorelin is stabilized 44-amino-acid GHRH analog — the longest GHRH sequence in common research use. They differ in molecular weight (711.85 vs 5135.86 g/mol) and in the pathways they are studied against.
Which is more cost-effective per milligram, Ipamorelin or Tesamorelin?
Ipamorelin is lower at approximately $4.90 per milligram at its best tier, against $5.93 for the other. Cost per milligram is only meaningful relative to the concentrations a given protocol requires, since these compounds are not used at comparable masses.
Can Ipamorelin and Tesamorelin be studied together?
Combination designs appear in the published literature for a number of these compounds. Whether it is appropriate for a given protocol depends entirely on the model and endpoint. We supply research compounds and do not provide protocol guidance — consult the primary literature for your specific model.
How should Ipamorelin and Tesamorelin be stored?
Store lyophilized powder at -20°C protected from light. Reconstituted solution stable at 2-8°C for up to 30 days. For Tesamorelin: Store lyophilized at -20°C protected from light. Reconstituted at 2-8°C for up to 30 days.
Which has the stronger evidence base?
Ipamorelin — Evidence base: small but well-defined. The selectivity result is clearly established and the receptor pharmacology is characterised. Primary evidence is concentrated in four papers from 1998 and 1999, with little added since. Tesamorelin — Evidence base: strong for the approved indication, supported by pooled phase 3 data with safety extension. Evidence outside that population and endpoint is limited, and the recent neurocognitive work is single-study.
All products sold on this website are intended for research and identification purposes only. These products are not intended for human dosing, injection, or ingestion.
Comparison generated from Lyra Vital catalog data. Every specification is reconciled against the certificate of analysis for the shipped batch.