Semaglutide
How to reconstitute the 20 mg vial and convert any target dose into insulin units. Semaglutide is the prescription drug Ozempic/Wegovy/Rybelsus, dosed once weekly per its FDA label (titrated to 2.0–2.4 mg). The approved product is a metered pen with no reconstitution; the math here is for research vials only.
Calculate for your vial
Enter the mg on your Semaglutide vial, the bacteriostatic water you added, and your target dose — it works out the exact units to draw on a U-100 insulin syringe, for whatever you personally have.
Reconstitution Calculator
Check the decimal. A misplaced decimal point here is a 10× dosing error. Re-read every number, and confirm your dose with a licensed clinician before you draw.
Educational only — not a dosing recommendation. This tool does the measurement math; it does not tell you what to take. On a U-100 insulin syringe, 100 units = 1 mL.
Dosing schedule
Semaglutide · fixed weekly step-up schedule
A fixed weekly titration ladder. Body weight and goal are context, not a formula — people with more to lose more often climb toward the 2.4 mg maintenance dose.
- 10.25 mg/wkWeeks 1–4Starting dose
- 20.5 mg/wkWeeks 5–8
- 31.0 mg/wkWeeks 9–12
- 41.7 mg/wkWeeks 13–16
- 52.4 mg/wkWeek 17+Maintenance / max
Everyone starts at 0.25 mg and steps up every 4 weeks on the same schedule — the ladder is not calculated from body weight. Someone with more to lose more often titrates toward the 2.4 mg maintenance dose, while a lighter person losing well with few side effects may hold at a lower step. The dose is individualized by tolerability and response under medical supervision, not from your weight.
Source: FDA label — Wegovy® (semaglutide). Educational only — not medical advice and not a dosing recommendation. Any dosing decision belongs with a licensed clinician.
1 · Find your dose
Pick what you're using Semaglutide for and how much bacteriostatic water you added — this pulls out the exact units to draw and how often people report using it.
Study staff will inject semaglutide, 0.5 mg alone in the morning after fasting under the skin of participants' thigh using a needle and a pen.
- How / how often
- Phase 1
Observational human-trial dose — studied, NOT a target or recommendation. Phase 1 (NCT03789578). Source: https://clinicaltrials.gov/study/NCT03789578
At 2 mL this 20 mg vial is 10 mg/mL (100 mcg per unit). Use the full matrix below to convert a specific amount into U-100 units — measurement math, not a recommendation.
2 · Reconstitute it cleanly, step by step
How to turn the 20 mg powder into a measured liquid with clean, sterile technique. More water means each insulin unit holds less peptide — easier to measure small amounts accurately.
1Swab the stoppers
Wipe the rubber top of each vial with an alcohol pad and let it air-dry.
2Draw the water
Pull your bacteriostatic water up into the insulin syringe.
3Reconstitute
Inject it slowly down the inside wall of the peptide vial — never straight onto the powder.
4Swirl to dissolve
Gently swirl until the powder fully dissolves into a clear liquid. Never shake.
5Equalize, then draw
To draw a dose: push in an equal amount of air first to equalize the pressure, then pull your dose.
- 1
Swab both tops
Wipe the rubber top of the bacteriostatic-water vial and the Semaglutide vial stopper with a fresh alcohol pad, and let them air-dry. Never touch the needle or the stoppers after wiping.
Alcohol swab · let dry - 2
Draw the water
First pull 2 mL of air into the syringe and inject it into the bacteriostatic-water vial to equalize the pressure, then draw your 2 mL of water back out. Inject it into the Semaglutide vial down the inside glass wall, not onto the powder.
2 mL BAC water - 3
Swirl, don't shake
Gently swirl the 20 mg vial until the powder fully dissolves into a clear liquid. Never shake — shaking can damage the peptide and foam the solution.
Swirl, don't shake - 4
Know your strength
The vial is now 10 mg/mL. Each unit on a U-100 syringe holds about 100 mcg.
10 mg/mL - 5
Re-swab & draw your dose
Wipe the stopper again. With a fresh insulin syringe, pull back 5 units of air and inject it into the vial to equalize the pressure, then draw 5 units (0.05 mL) for a 500 mcg dose.
5 units - 6
Store it right
Keep the mixed vial in the fridge, away from light. Use a new sterile syringe every time, never share, and drop used sharps in a proper container.
Refrigerate · fresh needle
What each water volume gives you:
3 · Full units reference
Every bacteriostatic-water volume (rows) against every target dose (columns) — each cell is the U-100 units and the exact draw in mL. The highlighted row is the easiest volume to measure.
| BAC water | Concentration | Per unit | 250 mcg | 500 mcg | 1 mg |
|---|---|---|---|---|---|
| 1 mL | 20 mg/mL | 200 mcg | 1.3u0.013 mL | 2.5u0.025 mL | 5u0.05 mL |
| 2 mLeasy pick | 10 mg/mL | 100 mcg | 2.5u0.025 mL | 5u0.05 mL | 10u0.1 mL |
| 3 mL | 6.67 mg/mL | 66.67 mcg | 3.8u0.037 mL | 7.5u0.075 mL | 15u0.15 mL |
4 · Everyday usage
Semaglutide is the FDA-approved prescription drug Ozempic/Wegovy/Rybelsus and is supplied as a finished, dose-metered pen — there is no patient reconstitution step for the approved product. The figures below are the approved-drug label titration schedule for reference only, not a recommendation to reconstitute a research vial.
Studied: Diabetes Mellitus, Type 2
Studied in trialsStudy staff will inject semaglutide, 0.5 mg alone in the morning after fasting under the skin of participants' thigh using a needle and a pen.
- Frequency
- Phase 1
Observational human-trial dose — studied, NOT a target or recommendation. Phase 1 (NCT03789578). Source: https://clinicaltrials.gov/study/NCT03789578
Studied: Healthy Volunteers
Studied in trialsSubjects will receive 1 dose of semaglutide 0.25 mg and 1 dose of dulaglutide 0.75 mg on the same day.
- Frequency
- Phase 4
Observational human-trial dose — studied, NOT a target or recommendation. Phase 4 (NCT04189848). Source: https://clinicaltrials.gov/study/NCT04189848
Studied: Obesity and Obesity-related Medical Conditions
Studied in trialsWegovy (semaglutide) will be provided as an induction dose of 0.25 mg, titrated up every 4 weeks to 0.5 mg, 1.0 mg, 1.7 mg and 2.4 mg, will be given, with a maintenance dose of 2.4 mg or to the maximum tolerated dose.
- Frequency
- Phase 4
Observational human-trial dose — studied, NOT a target or recommendation. Phase 4 (NCT06754163). Source: https://clinicaltrials.gov/study/NCT06754163
Frequently asked questions
How many insulin units is 250 mcg of Semaglutide from a 20 mg vial?
- Reconstituting a 20 mg vial with 2 mL of bacteriostatic water gives 10 mg/mL — about 100 mcg per unit. Drawing 250 mcg is 0.025 mL, or 2.5 units on a U-100 insulin syringe. This is measurement math, not a dose recommendation.
How many insulin units is 500 mcg of Semaglutide from a 20 mg vial?
- Reconstituting a 20 mg vial with 2 mL of bacteriostatic water gives 10 mg/mL — about 100 mcg per unit. Drawing 500 mcg is 0.05 mL, or 5 units on a U-100 insulin syringe. This is measurement math, not a dose recommendation.
Does the approved semaglutide product need reconstitution?
- No. Ozempic, Wegovy and Rybelsus are finished, FDA-regulated products — the injectables are supplied in metered pens and the oral form as tablets, with no patient mixing step. The reconstitution math here applies only to lyophilized research vials, which are not the approved medicine. Semaglutide is prescription-only; dosing belongs with a licensed clinician.
References
Note: the FDA-approved label in our dataset for Semaglutide is a non-injectable (oral) form, so it is not shown as the injection dose here; the figures above are the subcutaneous trial doses on record. The label link points to the approved oral product.
WikiPeps is a community reference. Reconstitution figures are deterministic measurement math; usage figures are sourced and labeled. Nothing here is medical advice, a recommendation, or an offer to sell peptides — dosing decisions belong with a licensed clinician.