PeptulatorReconstitution and dosing maths

Sermorelin dosage calculator

Sermorelin is dosed in micrograms, usually once a night.

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Dose to units at the usual vial and water

DoseU-100 unitsDrawDoses per vialVial lasts
100 mcg4 units0.04 mL5050 days
200 mcg8 units0.08 mL2525 days
300 mcg12 units0.12 mL1616 days
400 mcg16 units0.16 mL1212 days
500 mcg20 units0.2 mL1010 days

5 mg vial in 2 mL of bacteriostatic water (2.5 mg/mL), U-100 insulin syringe, once daily.

About Sermorelin

Sermorelin is a 29 amino acid fragment of growth hormone releasing hormone. It was once a licensed diagnostic and paediatric product and is now mostly seen through compounding pharmacies and research vendors. It has a very short half-life, which is why it is dosed close to sleep, when the natural growth hormone pulse occurs.

A 5 mg vial reconstituted with 2 mL gives 2,500 mcg/mL, so 200 mcg is 0.08 mL, or 8 units. Compounded sermorelin from a pharmacy often comes already reconstituted at a stated concentration, in which case skip the vial and water fields and use the mg to units page with the concentration printed on the label.

The same 5 mg vial at other water volumes

If the draw is awkward to read, change the water, not the dose. The dose stays the same; only the mark moves.

VialBAC waterConcentrationDrawU-100 unitsDoses/vial
5 mg1 mL5 mg/mL0.04 mL4 units25
5 mg2 mL2.5 mg/mL0.08 mL8 units25
5 mg3 mL1.67 mg/mL0.12 mL12 units25
10 mg1 mL10 mg/mL0.02 mL2 units50
10 mg2 mL5 mg/mL0.04 mL4 units50
10 mg3 mL3.33 mg/mL0.06 mL6 units50

All rows above assume a 200 mcg dose and a standard U-100 insulin syringe, where 100 units = 1 mL.

How long it lasts in the body

The half-life of Sermorelin is about 12 minutes. That is the time for the amount in your blood to halve, so after one half-life you are at 50 percent of the peak, after two you are at 25 percent, and after four you are at roughly 6 percent. It is gone within an hour or two. What it triggers (a growth hormone pulse, for instance) lasts longer than the peptide itself, which is why timing matters more than the exact number of minutes.

100%75%50%25%0%one half-life0 min12 min24 min36 min48 min

Common questions

How many units is 200 mcg of Sermorelin?
It depends entirely on how much water you added. In a 5 mg vial reconstituted with 2 mL, the concentration is 2.5 mg/mL, so 200 mcg is 0.08 mL, which is 8 units on a U-100 insulin syringe. In the same vial with 1 mL of water it is 4 units, and with 3 mL it is 12 units.
How much bacteriostatic water for a 5 mg Sermorelin vial?
2 mL is the usual choice. It gives 2.5 mg/mL, which puts the commonly reported range of 100 mcg to 500 mcg between roughly 4 and 20 units. Aim for a draw between about 10 and 50 units, where the barrel is easiest to read, and add or remove water to get there.
How many doses are in a 5 mg vial?
Divide 5 by your dose. At 200 mcg that is 25 doses, which at once daily is 25 days.
How many units is 200 mcg of sermorelin?
In a 5 mg vial with 2 mL of water, 8 units. In the same vial with 1 mL, 4 units.
My sermorelin came as a liquid. How do I use the calculator?
Use the concentration on the label. If it says 3 mg/mL, that is the same as a 3 mg vial reconstituted with 1 mL. Enter those two numbers and your dose.
IndependentThis site does not sell peptides and is not owned by a vendor.
The maths is openThe formula is on every page and in the methodology. The code is one file with an automated test suite, run before each deploy.
How it earnsAffiliate links on one marked page, never inside the calculator.
ReviewedDose ranges and half-lives checked 3 September 2026.

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The where to buy page lists the vendors this site uses and what to check first. Peptide Bureau keeps the ranked scorecard.

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Tools

Before you use these numbers This is a unit-conversion tool. It turns a vial strength and a water volume into a concentration, a draw volume and a syringe mark. It does not tell you what to take, whether to take it, or whether a compound is safe for you. Most compounds listed are sold for laboratory research and are not approved for human use. Nothing here is medical advice. Dosing decisions belong with a licensed clinician who knows your history. Always check the strength printed on your own vial rather than trusting a preset.