Semaglutide reconstitution calculator

Semaglutide at a glance

10mg vial + 2mL BAC water = 5 units = 250mcg — Frequency: weekly — Best taken: same day each week, any time

Full Semaglutide dosing reference — reconstitution per vial size, dose-to-units table, side effects and sources.

What it does

• Activates GLP-1 receptors on vagus nerve endings in the gut wall, which relay a fullness signal up to the brainstem and on to the hypothalamus — the brain's appetite-control center.
• That hypothalamic signal tells the brain to end a meal earlier than it otherwise would, lowering how much food it takes to feel satisfied.
• Slows gastric emptying — food leaves the stomach more slowly, which stretches out the feeling of fullness after eating.
• FDA-approved (as Ozempic/Wegovy) for type 2 diabetes and chronic weight management.
• Large clinical trials show significant, sustained weight loss and improved blood sugar control.
• Also studied for reducing cardiovascular risk in people with existing heart disease.
• The current Wegovy label (June 2026) allows increasing to a maximum of 7.2 mg once weekly for adults who tolerate 2.4 mg for at least 4 weeks; the amounts listed here stop at 2.4 mg.

Slows gastric emptying, which changes how other oral medications are absorbed. The roughly one-third rise in thyroid medication (levothyroxine) exposure comes from the oral semaglutide tablet label, where the tablet's absorption enhancer is part of the mechanism — the injectable label carries no levothyroxine data at all. Combined with insulin or a sulfonylurea, the added blood-sugar-lowering effect can cause hypoglycemia — those doses often need to be reduced first. Talk to your prescribing doctor before combining.

Notes

Listed titration schedule: weeks 1-4 250mcg, weeks 5-8 500mcg, weeks 9-12 1000mcg, weeks 13-16 1700mcg, weeks 17+ 2400mcg (maintenance). The 10mg reference vial mixes to 5mg/mL. Larger vial size options are capped at ~3mL BAC water instead of diluted further, so they come out more concentrated (fewer units per dose) than this reference size.

Side Effects

• Nausea — up to half of users, mostly during dose increases.
• Diarrhea (~1 in 4), constipation (~1 in 3).
• Vomiting, abdominal pain.
• Usually mild; slower titration is reported to help.

Semaglutide vial sizes and concentrations

Standard water for each Semaglutide vial size in the Dosify Me data, and the concentration it gives. One unit is 0.01 mL on a U-100 insulin syringe.

^* This size is conventionally mixed more concentrated rather than diluted further — fewer units per dose than smaller vials of this peptide.

Syringe units for the listed quantities, by vial size

Worked example for Semaglutide

1. The example vial: 20 mg of Semaglutide, mixed with 3.00 mL of bacteriostatic water.
2. Concentration: 20 mg ÷ 3.00 mL = 6.67 mg/mL.
3. One syringe unit is 0.01 mL, so it holds 6.67 mg/mL × 0.01 mL = 0.067 mg (66.67 mcg).
4. Example quantity: 250 mcg = 0.25 mg.
5. Volume: 0.25 mg ÷ 6.67 mg/mL = 0.0375 mL.
6. Syringe reading: 0.0375 mL × 100 = 3.8 units.

Label numbers from the Dosify Me data, used to show the arithmetic. Not a recommendation of any quantity.

Frequently asked

How many units is 250 mcg of Semaglutide?

At 5 mg/mL (the standard mix for vials up to 10 mg), 250 mcg of Semaglutide is 5.0 units on a 100-unit insulin syringe (0.050 mL).

How many units is 500 mcg of Semaglutide?

At 5 mg/mL (the standard mix for vials up to 10 mg), 500 mcg of Semaglutide is 10.0 units on a 100-unit insulin syringe (0.100 mL).

How many units is 1 mg of Semaglutide?

At 5 mg/mL (the standard mix for vials up to 10 mg), 1 mg of Semaglutide is 20.0 units on a 100-unit insulin syringe (0.200 mL).

How much bacteriostatic water do I add to a 5 mg vial of Semaglutide?

1.00 mL, which gives 5 mg/mL. Larger vials hold at most 3 mL of water, so they are mixed more concentrated and need fewer units per dose.

How much bacteriostatic water do I add to a 10 mg vial of Semaglutide?

2.00 mL, which gives 5 mg/mL. Larger vials hold at most 3 mL of water, so they are mixed more concentrated and need fewer units per dose.

How much bacteriostatic water do I add to a 20 mg vial of Semaglutide?

3.00 mL, which gives 6.67 mg/mL. This size holds at most 3 mL of water, so it is mixed more concentrated and the same dose is fewer units than from a smaller vial.

How often is Semaglutide taken?

Weekly. Same day each week, any time of day Typical cycle: Often run continuously; tapering is done under guidance.

Is “sema” the same as Semaglutide?

Yes. “sema” is the short name people use for Semaglutide in forums and search, and every figure on this page is for that same compound. The units, water and schedule above do not change with the spelling.

Related pages and guides

• Semaglutide dosing reference
• How many units is 250 mcg?
• How much bacteriostatic water for a 5 mg vial?
• U-100 vs U-50 insulin syringe for peptides
• Peptide injection site rotation
• All peptide guides

Other calculators

General peptide calculator · BAC water calculator · Peptide dosing chart · How to reconstitute peptides · mcg to units chart