GHRP-2 reconstitution calculator.
A 5 mg vial of GHRP-2 dissolved in 2 mL of bacteriostatic water is 2,500 mcg per mL, which is 25 mcg per unit on a U-100 insulin syringe.
GHRP-2, also called pralmorelin, is approved in Japan only as a single-dose diagnostic test for growth hormone deficiency, and nowhere as a treatment, so no labeled presentation describes a multi-draw vial. Research vials are 5 mg and 10 mg against amounts discussed in the low hundreds of micrograms, which puts draws in the first few units of the syringe, and on the 10 mg vial right at the edge of what can be read.
Reference range often cited for GHRP-2: 100–300 mcg, shown for orientation only, not a recommendation. Enter your own target below. Read the evidence →
Each unit on a 100u · 1.0 mL syringe ≈ 25 mcg of this solution.
Show the math
More water → lower concentration → more units for the same amount.
How much bacteriostatic water for a GHRP-2 vial?
There is no single correct volume. More water gives a weaker solution, so each unit on the syringe holds less GHRP-2 and a given amount takes more units to measure, which is easier to read on the syringe scale. Less water does the opposite. These tables show the concentration for each common vial size across the usual volumes. They are arithmetic, not a recommendation of how much to take.
| BAC water | Concentration | Per 1 unit | Per 10 units |
|---|---|---|---|
| 1 mL | 5,000 mcg/mL | 50 mcg | 500 mcg |
| 1.5 mL | 3,333 mcg/mL | 33.3 mcg | 333 mcg |
| 2 mL | 2,500 mcg/mL | 25 mcg | 250 mcg |
| 2.5 mL | 2,000 mcg/mL | 20 mcg | 200 mcg |
| 3 mL | 1,667 mcg/mL | 16.7 mcg | 167 mcg |
| BAC water | Concentration | Per 1 unit | Per 10 units |
|---|---|---|---|
| 1 mL | 10,000 mcg/mL | 100 mcg | 1,000 mcg |
| 1.5 mL | 6,667 mcg/mL | 66.7 mcg | 667 mcg |
| 2 mL | 5,000 mcg/mL | 50 mcg | 500 mcg |
| 2.5 mL | 4,000 mcg/mL | 40 mcg | 400 mcg |
| 3 mL | 3,333 mcg/mL | 33.3 mcg | 333 mcg |
How many units of GHRP-2 is a given amount?
Divide the amount in micrograms by the micrograms per unit for your mix. With a solution of 2,500 mcg per mL, one unit on a U-100 syringe holds 25 mcg, so any amount in mcg divided by 25 gives the units. The calculator above does this for you from your own vial and water, and the tables give the per-unit figure for each common mix.
Why does GHRP-2 need its own calculation?
- 5 mg in 2 mL is 2,500 mcg/mL, so 100 mcg is 4 units. 10 mg in the same 2 mL is 5,000 mcg/mL, where 100 mcg is 2 units, the threshold below which the calculator warns about measurement error.
- More water is the fix. 5 mg in 5 mL is 1,000 mcg/mL, so the same 100 mcg reads as 10 units.
- GHRP-2 acts on the ghrelin receptor and is often discussed alongside a GHRH analog such as Mod-GRF 1-29, which comes in smaller vials. Two vials means two concentrations, and unit counts that never carry across.
- At four units or fewer, the syringe matters. The same volume fills a larger share of a 30 unit barrel than a 100 unit one, and the calculator's syringe selector shows how far up each barrel the draw reaches.
How is GHRP-2 administered, and what does the math look like?
How GHRP-2 is actually administered, with the concentration arithmetic written out. Amounts in these tables are illustrative examples of the math, never a recommendation.
GHRP-2: research formats
Choose the format you are researching to see route-specific notes.
Potent ghrelin mimetic; stimulates GH and appetite. Typically 3× daily at evenly spaced intervals.
GHRP-2 is sold as a 5 mg vial. Reconstituting 5 mg with 2.0 mL BAC water gives a concentrated 2,500 mcg/mL solution, with small injection volumes per dose. Research protocols commonly use GHRP-2 up to three times daily (morning, pre-workout, and pre-sleep).
At 2,500 mcg/mL, volumes are small and precise drawing is essential. A TB syringe (marked in mL) can be easier to read accurately than a U-100 at these tiny volumes.
GHRP-2 causes appetite stimulation; this is more pronounced than with ipamorelin and is a key differentiator between the two compounds.
GHRP-2 reconstitution: common questions
How many units is 100 mcg of GHRP-2?
On 5 mg in 2 mL (2,500 mcg/mL) it is 4 units. On 5 mg in 5 mL (1,000 mcg/mL) it is 10 units. Same amount, different readability.
Is GHRP-2 approved anywhere?
In Japan, as a single-dose diagnostic agent for assessing growth hormone deficiency, and not as a therapy. It is not FDA-approved for any use and is prohibited in sport by WADA. The legal status page covers the rest.
Why is my GHRP-2 draw only 2 units?
A 10 mg vial in a small volume is concentrated relative to microgram figures. Small draws carry proportionally more reading error, so adding water to spread the same amount across more of the barrel is the usual fix.
What the evidence on GHRP-2 actually shows
Knowing the concentration is not the same as knowing whether to use it. These are the strongest studies behind the GHRP-2 profile, labelled with the study type PubMed itself assigns.
- Observational study · 1997Effects of GHRP-2 and hexarelin, two synthetic GH-releasing peptides, on GH, prolactin, ACTH and cortisol levels in man. Comparison with the effects of GHRH, TRH and hCRHPeptides · PMID 9285939
- Journal article · 2005Growth hormone releasing peptide-2 (GHRP-2), like ghrelin, increases food intake in healthy menThe Journal of clinical endocrinology and metabolism · PMID 15699539
This page is arithmetic on numbers you enter. It does not recommend an amount of GHRP-2, and nothing here is medical advice. For what the published evidence actually supports, read the GHRP-2 profile, and for regulatory status see is GHRP-2 legal. Reviewed June 1, 2026.
Different question? The general reconstitution calculator covers every compound on the site, the blend calculator handles multi-peptide stacks, and vial longevity turns a vial into weeks of supply.
PepCue remembers your GHRP-2 vial, concentration, and draw, then tracks every dose against it. Free.