Peptide Research
GHRP-2 (Pralmorelin): The Middle Option in the GHRP Family
GHRP-2 sits between ipamorelin and hexarelin on both potency and side effects — which makes it the clearest illustration of the trade-off running through the whole family.
Peptide Library Editorial · September 25, 2026 · 2 min read
GHRP-2, also called pralmorelin, is a six-amino-acid growth hormone releasing peptide. It sits between ipamorelin and hexarelin on both potency and selectivity, which makes it the clearest illustration of the trade-off running through the whole family.
Not an approved drug. GHRP-2, as sold for research has no approved human indication in the US, EU, or UK and no established human dose. It is sold for laboratory research only, and nothing here is dosing guidance.
The family trade-off
Ipamorelin | GHRP-2 | GHRP-6 | Hexarelin | |
|---|---|---|---|---|
GH response | Moderate | High | High | Highest |
Cortisol / prolactin | Minimal | Some increase | Some increase | Notable increase |
Appetite stimulation | Minimal | Moderate | Marked | Moderate |
Desensitisation | Slowest | Moderate | Moderate | Fastest |
Reading across that table is the useful exercise. Potency and unwanted activity rise together, which is why ipamorelin remains the most discussed despite producing the smallest response, and why hexarelin is not simply the best because it is the strongest.
Why appetite comes up
GHRPs act on the ghrelin receptor, and ghrelin is the hunger hormone. Appetite stimulation is not a side effect in the incidental sense — it is the receptor doing another of its jobs.
GHRP-6 is most associated with this and GHRP-2 less so, but the mechanism is shared. MK-677 acts on the same receptor and is well known for it.
It has a diagnostic history
Pralmorelin has been used as a diagnostic agent in growth hormone stimulation testing — administering a known amount and measuring the GH response to assess pituitary function.
That is worth distinguishing from therapeutic use, in the same way kisspeptin is mostly a diagnostic probe. A single controlled administration to generate a measurement is a different application from repeated use for an effect, and published "doses" often come from the former.
The vial math
Supplied lyophilised, commonly in 5 mg or 10 mg vials, with figures discussed in micrograms.
Vial | BAC water | Concentration | 100 mcg | 200 mcg | 300 mcg |
|---|---|---|---|---|---|
5 mg | 2 mL | 2.5 mg/mL | 4 units | 8 units | 12 units |
5 mg | 3 mL | 1.67 mg/mL | 6 units | 12 units | 18 units |
5 mg | 5 mL | 1 mg/mL | 10 units | 20 units | 30 units |
10 mg | 5 mL | 2 mg/mL | 5 units | 10 units | 15 units |
The peptide calculator converts any vial and target into units.
Storage
Storage is the same as any reconstituted vial: 2–8 °C, protected from light, never frozen, and bounded by the shorter of peptide stability and the 28-day limit on bacteriostatic water. The bacteriostatic water guide covers the detail.
Frequently asked questions
Is GHRP-2 better than ipamorelin?
It produces a larger GH response and less selectivity. Which matters more depends on what you are trying to observe — "better" is not a property of the molecule.
What is the difference from GHRP-6?
Both are GHRPs with similar potency. GHRP-6 is more strongly associated with appetite stimulation.
Why is it paired with a GHRH analogue?
Different receptors, complementary signalling. See ipamorelin vs sermorelin.
Research and educational use only. Peptide Library is an independent research and comparison platform and does not sell peptides. Nothing here is medical advice, dosing guidance, or a recommendation to administer any substance to a person or an animal. Consult a licensed clinician for anything concerning human health.
Sources
- 1. The emerging landscape of performance-enhancing peptides modulating GH-IGF1 axis: bridging the gap between clinical evidence and patient self-administration — Frontiers in Endocrinology (2026) Source PubMed
- 2. Raun K, et al. Ipamorelin, the first selective growth hormone secretagogue — European Journal of Endocrinology (1998) Source PubMed
Author
Peptide Library Editorial
Editorial content from Peptide Library. Research and educational use only. Not medical advice.
Related articles
Related peptides
Related tools
Research smarter with Peptide Library.
Compare peptides, review vendor data, and use research calculators in one place.
Explore the LibraryResearch and educational use only. Not medical advice. Peptide Library does not sell peptides.