GHRP-1 reconstitution calculator.
A 5 mg vial of GHRP-1 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-1 is the least documented of the original growth hormone-releasing peptides: its published human work is acute intravenous testing from the early 1990s, and nothing published describes a reconstituted vial at all. Vials are 5 mg and 10 mg, and with no reference figure to check against, every number on this page is purely your own arithmetic.
Reference range often cited for GHRP-1: 100–200 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-1 vial?
There is no single correct volume. More water gives a weaker solution, so each unit on the syringe holds less GHRP-1 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-1 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-1 need its own calculation?
- 5 mg in 2 mL is 2,500 mcg/mL, so 100 mcg is 4 units. A 10 mg vial in the same water is 5,000 mcg/mL, where the same 100 mcg is just 2 units.
- GHRP-1 is a seven amino acid peptide, while GHRP-2 and GHRP-6 are six. Near-identical names and identical vial sizes make it easy to read the wrong chart or misread a label, and the arithmetic will not catch that.
- The calculator trusts the mass and identity on the label. GHRP-1 is unregulated research material, and the profile covers why neither is verified for it.
How is GHRP-1 administered, and what does the math look like?
How GHRP-1 is actually administered, with the concentration arithmetic written out. Amounts in these tables are illustrative examples of the math, never a recommendation.
GHRP-1: research formats
Choose the format you are researching to see route-specific notes.
Same GHRP-class format as GHRP-2 and GHRP-6; the original human studies used the IV route.
GHRP-1 is one of the original growth hormone-releasing peptides from Bowers' lab and is sold today only as a research-grade lyophilized vial, commonly 5 mg. Reconstituting 5 mg with 2.0 mL BAC water gives 2,500 mcg/mL, the same concentrated format used for its better-known siblings GHRP-2 and GHRP-6.
The published human work on GHRP-1 (Laron and Bowers, 1993) used intravenous administration in an acute pituitary-response setting, not repeated subcutaneous use. There are no controlled trials of chronic GHRP-1 administration by any route.
GHRP-1 has far less human data than GHRP-2 or GHRP-6, and material sold online is unregulated research-grade product of uncertain identity and purity.
GHRP-1 reconstitution: common questions
How many units is 200 mcg of GHRP-1?
On 5 mg in 2 mL (2,500 mcg/mL) it is 8 units. On 5 mg in 5 mL (1,000 mcg/mL) it is 20 units.
Is there an official GHRP-1 reconstitution instruction?
No. GHRP-1 was never developed into a drug, so there is no label, no manufacturer instruction, and no approved presentation. Any concentration you see quoted is someone else's arithmetic on their own vial.
Is GHRP-1 the same as GHRP-2 or GHRP-6?
No. All three act on the ghrelin receptor, but they are different sequences, and GHRP-1 has far less human data than either sibling. Only the arithmetic is shared, and only when the vial and water match.
What the evidence on GHRP-1 actually shows
Knowing the concentration is not the same as knowing whether to use it. These are the strongest studies behind the GHRP-1 profile, labelled with the study type PubMed itself assigns.
- Journal article · 1999Ghrelin is a growth-hormone-releasing acylated peptide from stomachNature · PMID 10604470
- Journal article · 1998Ipamorelin, the first selective growth hormone secretagogueEuropean journal of endocrinology · PMID 9849822
- Journal article · 1993Growth hormone-releasing activity of growth hormone-releasing peptide-1 (a synthetic heptapeptide) in children and adolescentsActa endocrinologica · PMID 8279223
This page is arithmetic on numbers you enter. It does not recommend an amount of GHRP-1, and nothing here is medical advice. For what the published evidence actually supports, read the GHRP-1 profile, and for regulatory status see is GHRP-1 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.
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