Kisspeptin-10 Reconstitution: Water, mcg/mL and Units

Kisspeptin-10 is the ten-amino-acid end of the kisspeptin hormone, studied in people as a way to stimulate the reproductive axis. Its research vials hold milligrams; the human studies gave tens of micrograms, into a vein, from solutions prepared for the purpose. This page works the concentration and micrograms per unit for the common vials and water volumes, measures the distance between those solutions and the ones the studies used, and reports what is and is not known about how long kisspeptin-10 lasts. It reports; it states no amount and no water volume to use.

The study doses themselves, with their routes and the vendor figures, are on the kisspeptin-10 dosage page; its comparisons with related compounds are on gonadorelin vs kisspeptin and how it compares with PT-141.

Concentration by vial and water

Concentration is the vial amount divided by the water; micrograms per unit on a U-100 syringe is that figure divided by 100.

The three amount columns are the 70 kg conversions of the published intravenous doses, as worked on the kisspeptin-10 calculator page: 0.24 nmol/kg (21.9 mcg), 1 mcg/kg (70 mcg) and 1 nmol/kg (91.2 mcg). They are listed because they are the figures people convert, converted, not endorsed. Even at 5 mL of water, the most dilute row, none of them reaches ten units.

How far a vial sits from the study solutions

The registry records describe what the studies actually prepared. NCT03771326, a completed 14-man study at Quaid-e-Azam University, gave kisspeptin-10 "intravenously administered (0.5µg/kg BW, prepared under sterile conditions), as a bolus in a volume of 1ml". NCT03315325, a completed 15-man study by the same university, gave a single intravenous bolus of 1 mcg/kg. At 70 kg those are 35 and 70 mcg, and if both were given in 1 mL, solutions of 35 and 70 mcg/mL.

The second row assumes the 1 mL volume stated for the first study; NCT03315325 does not give its volume. The comparison is arithmetic on the registry text.

Turned around, the question becomes how much water would make a study amount readable. A 10-unit reading of 70 mcg needs 700 mcg/mL, which is 7.1 mL of water in a 5 mg vial and 14.3 mL in a 10 mg vial. A 10-unit reading of 21.9 mcg needs 219 mcg/mL, which is 22.8 mL in a 5 mg vial. These figures are the reason the studies used prepared intravenous solutions rather than anything resembling a research vial: at the volumes a vial is mixed with, the amounts sit below the first few marks, where a half-unit misreading is an error of 10% or more. The insulin syringe units page shows the marks on 30-, 50- and 100-unit barrels.

How many study-sized amounts a vial holds

The water changes how an amount reads; it does not change how many amounts the powder contains. At 1,302.4 g/mol a 5 mg vial holds about 3,840 nmol and a 10 mg vial about 7,680.

The counts are arithmetic on the vial labels; none is a course. They show that a single research vial holds more than an entire small study gave its participants.

What is known about how long it lasts

In plasma, very little time. A 2013 study by Liu and colleagues, which built the first mass-spectrometry assay for kisspeptin-10 (PMID 23524040), incubated it in rat plasma and found initial decomposition half-lives of 6.78 minutes at 4 °C, 2.91 minutes at 25 °C and 1.69 minutes at 37 °C. The main breakdown product was kisspeptin-10 minus its first amino acid, tyrosine, and adding a protease inhibitor to the plasma largely prevented the loss. After a 1 mg/kg intravenous dose in rats it was detectable only in the first few minutes.

The same paper cites the human figure: after an intravenous infusion, the half-life of kisspeptin-10 measured by radioimmunoassay was 3.8 to 4.1 minutes, against 27.6 minutes for the longer kisspeptin-54. A 2017 mouse study (PMID 28464043) found about 4 and 32 minutes for the two forms, and found that repeating kisspeptin-10 every ten minutes for an hour still did not reproduce the sustained hormone rise one kisspeptin-54 dose gave.

None of this describes a vial. The breakdown in plasma is the work of enzymes, which bacteriostatic water does not contain, and no study of kisspeptin-10 kept in bacteriostatic water, at any temperature, was found. How long a mixed vial keeps is therefore unknown; the general storage of peptides is on Medibact's how to store peptides page.

Status and what this page does not do

No kisspeptin product is approved, and FDA had placed kisspeptin-10 in Category 2 of its 503A bulk-substance list, the category for substances that raise significant safety risks, as this site recorded on 2026-09-18. This page does not state an amount, a water volume or a storage time. It works the concentration for each volume and reports what the studies and the stability work measured. The mixing steps are on Medibact's how to reconstitute peptides page, the arithmetic for any other vial on the reconstitution calculator, and the compound in Medibact's Kisspeptin-10 guide. Decisions about administering anything belong with a clinician.

Sources and dates

Opened 2026-10-29: ClinicalTrials.gov records NCT03771326 (last updated 2018-12-12), NCT03315325 (2017-10-23) and NCT03286517 (2017-09-18) and the search "kisspeptin-10" (5 records); full text of Liu Z et al., J Chromatogr B 2013;926:1-8 (PMID 23524040, PMC3955120), sections 2.5, 3.4 and 3.5 and Table 2; abstract of d'Anglemont de Tassigny X et al., PLoS One 2017;12(5):e0176821 (PMID 28464043). Carried from this site's kisspeptin-10 pages with their read dates: the molecular weight (PubChem CID 25240297), the 0.24 and 1 nmol/kg and 1 mcg/kg study conversions, and the FDA status (2026-09-18). Concentration, dilution and per-vial arithmetic by this site. Corrections go to the contact page.