Peplo · Reconstitution calculator

Semaglutide

GLP-1 receptor agonist (Wegovy/Ozempic); about 15% mean weight loss at 2.4 mg in the STEP-1 trial.

metabolic
Reconstitution calculator
mg

The total peptide in the vial — the mg number on the label (e.g. 5 mg). This is your whole supply, not one dose.

mL

The sterile water you add to dissolve the powder (this is called reconstituting). More water makes small doses easier to measure.

mg

How much you take in one injection. 1 mg = 1000 mcg.

Draw to 10 units

0.10 mL on a U-100 insulin syringe

A starting reference, not medical advice — see how we source this.

Half-life
~168 h
Route
SubQ
Storage
Refrigerate 2–8°C; use within 28–30 days. Do not freeze. (~30 days)
Citations
1 referenced

US regulatory status

Semaglutide is approved by the FDA as Ozempic (type 2 diabetes) and Wegovy (chronic weight management).

What is Semaglutide?

Semaglutide is a GLP-1 receptor agonist. It mimics the incretin hormone GLP-1, which has been studied for its role in glucose regulation, appetite signaling, and gastric emptying.

How Semaglutide works

Activates the GLP-1 receptor to suppress appetite and slow gastric emptying. Dosed once weekly subcutaneously with a 5-step monthly escalation to a 2.4 mg maintenance dose.

What the research says

Semaglutide is among the most extensively studied compounds in this catalog. The STEP program of randomized controlled trials evaluated its effect on body weight, the SUSTAIN trials examined glycemic endpoints in type 2 diabetes, and the SELECT trial assessed cardiovascular outcomes. The primary trial reports are linked in the references below.

  1. 2021Once-Weekly Semaglutide in Adults with Overweight or Obesity (STEP 1)

Evidence limitations

This summary reflects the specific studies cited here and is not a complete account of the compound's clinical literature.

Safety & use boundary

Semaglutide is a prescription medication and should only be used under the supervision of a licensed clinician. Gastrointestinal effects during dose titration are commonly described in the trial literature. This page is educational and is not medical advice.

Published protocols

Dosing figures reported in the cited research. Educational reference, not a recommendation.

How to reconstitute Semaglutide

New to this? Here's the whole process, start to finish. Educational only — not medical advice.

What you'll need

  • The Semaglutide vial — a small glass vial of white, freeze-dried powder
  • Bacteriostatic water — the liquid you mix in (not plain sterile or tap water)
  • U-100 insulin syringes — the small syringes marked in units
  • Alcohol swabs to wipe the vial tops before you touch them with a needle
  • A spot in the fridge to keep it once it's mixed

Step by step

  1. Wipe everything down

    Swab the rubber top of both the peptide vial and the bacteriostatic water with an alcohol wipe. Clean tops are what keep the mixed solution good for weeks instead of days.

  2. Draw the water

    Use the calculator above to see how much bacteriostatic water to add for your vial size. Pull exactly that amount out of the water vial with a syringe.

  3. Add it slowly

    Push the needle into the peptide vial and let the water run gently down the inside glass wall — don't blast it straight onto the powder.

  4. Let it dissolve

    Swirl the vial gently or just let it sit. The powder goes into solution on its own in a minute or two. Never shake it hard.

  5. Read your draw

    Enter your vial size, the water you added, and your dose in the calculator. It shows the exact units to pull into your syringe — you never do the math yourself.

  6. Store it cold

    Cap it and keep it in the fridge. Semaglutide stays good for about 30 days once it's mixed.

Reading your dose

The calculator gives you a number like “Draw to 20 units.” Units are just the numbered marks on a U-100 insulin syringe (100 units fill 1 mL). “20 units” means pull the plunger back to the 20 mark. You don't convert milligrams to micrograms in your head — that's the whole point of the calculator. If you're brand new to injecting, learn proper technique and site rotation from a qualified clinician or nurse before your first dose; this page covers the mixing and measuring, not the injection itself.

Storing it

Before mixing: Lyophilized powder — refrigerate 2–8°C; protect from light. Once reconstituted: Refrigerate 2–8°C; use within 28–30 days. Do not freeze. (about 30 days). Don't freeze a reconstituted vial.

What “cycling” means

Many peptides are used in “cycles” — a stretch of daily or weekly use (“on”), then a break (“off”), rather than continuously. Cycling gives the body a rest and is a common pattern in the research. Any specific on/off lengths for a compound live in its published protocols above, drawn from the cited studies — this site shows you what the research used, it doesn't recommend a schedule for you.

Common first-timer mistakes

  • Shaking the vial to mix it

    Swirl it gently or just let it sit. Shaking can damage delicate peptides — you want the powder to dissolve, not foam.

  • Using tap water or plain sterile water

    Use bacteriostatic water. Plain sterile water has no preservative, so a mixed vial spoils in a day or two instead of lasting weeks.

  • Leaving a mixed vial on the counter

    Keep reconstituted vials in the fridge. Heat and light break the peptide down faster.

  • Eyeballing the dose instead of measuring

    Use the calculator and draw to the exact unit mark on the syringe. Guessing a tiny volume is where most measuring errors happen.

  • Reusing needles

    Use a fresh syringe each time. A used needle is duller, hurts more, and is no longer sterile.

  • Mixing up mg and mcg

    1 mg = 1000 mcg. The calculator keeps them straight so you don't have to — just enter your dose in the unit it asks for.

Words you'll see

Reconstitution
Mixing a freeze-dried peptide powder with liquid (bacteriostatic water) so it can be drawn into a syringe.
Bacteriostatic water
Sterile water with a tiny amount of benzyl alcohol that stops bacteria growing, so a mixed vial keeps for weeks. Not the same as plain sterile water.
U-100 insulin syringe
A small syringe marked in “units,” where 100 units = 1 mL. Peptide draws are measured in these units.
Subcutaneous (SubQ)
An injection into the fatty layer just under the skin, rather than into muscle or a vein.
mcg vs mg
1 mg = 1000 mcg. Doses are often written in micrograms (mcg); the calculator handles the conversion for you.
Lyophilized
Freeze-dried. The powder in the vial is the peptide with its water removed so it stays stable on the shelf.
Half-life
Roughly how long it takes your body to clear half of a dose — a rough sense of how long it stays active.

Common questions

What is Semaglutide?

GLP-1 receptor agonist (Wegovy/Ozempic); about 15% mean weight loss at 2.4 mg in the STEP-1 trial. Activates the GLP-1 receptor to suppress appetite and slow gastric emptying. Dosed once weekly subcutaneously with a 5-step monthly escalation to a 2.4 mg maintenance dose.

How is Semaglutide reconstituted?

Semaglutide ships as a lyophilised powder and is reconstituted with bacteriostatic water before use, then drawn on an insulin syringe. Use the calculator above to see the exact units to draw for your vial size and dose. This is a reference tool, not medical advice.

What is the half-life of Semaglutide?

Research reports an approximate half-life of 168 hours for Semaglutide. Half-life informs how frequently a compound is studied; it is not a dosing instruction.

How should Semaglutide be stored?

Lyophilized powder — refrigerate 2–8°C; protect from light. Once reconstituted: Refrigerate 2–8°C; use within 28–30 days. Do not freeze. (about 30 days). This is general storage information, not medical advice.

Keep your protocol, doses, and vials in one place.

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Semaglutide Reconstitution Calculator, Dosing & Storage | Peplo