Semaglutide Units to mg: 20, 40 and 50 Units Explained
How many mg is 20, 40 or 50 units of semaglutide? Conversion charts in both directions for every common vial concentration, plus how to read your syringe.
By
NativeMed
Medically reviewed by
Dr. Michael Wasef, MD
Published
· Last reviewed
Key Takeaways
50 units of semaglutide is 1.25 mg at 2.5 mg/mL, 0.5 mg at 1 mg/mL and 2.5 mg at 5 mg/mL.
Units to mg: units ÷ 100 × concentration in mg/mL. mg to units: dose ÷ concentration × 100.
The same number of units can be five times more medication from one vial than another, so always check your label.
Branded Wegovy and Ozempic pens are set in mg, so units only apply to multi-dose vials.
50 units of semaglutide is 1.25 mg if your vial's concentration is 2.5 mg/mL. At 1 mg/mL it's 0.5 mg, and at 5 mg/mL it's 2.5 mg. The number of units only tells you the dose once you know your vial's concentration, which is printed on the label.
This page answers the most common questions (20, 40 and 50 units) and has full conversion tables in both directions, plus how to read your syringe.
Important: this is general information. Always follow your prescription label and your provider's instructions. If your numbers don't match what you expect, ask your provider or pharmacist before injecting.
The formula
A U-100 insulin syringe holds 100 units per milliliter (mL), so 1 unit is 0.01 mL. To convert:
units to mg: units ÷ 100 × concentration in mg/mL
mg to units: dose in mg ÷ concentration in mg/mL × 100
Example: you draw 20 units from a 2.5 mg/mL vial. That's 20 ÷ 100 × 2.5 = 0.5 mg.
Semaglutide units to mg
Semaglutide units to mg on a U-100 syringe, by vial concentration
Units | 1 mg/mL | 2.5 mg/mL | 5 mg/mL |
|---|---|---|---|
5 units | 0.05 mg | 0.125 mg | 0.25 mg |
10 units | 0.1 mg | 0.25 mg | 0.5 mg |
20 units | 0.2 mg | 0.5 mg | 1 mg |
25 units | 0.25 mg | 0.625 mg | 1.25 mg |
30 units | 0.3 mg | 0.75 mg | 1.5 mg |
40 units | 0.4 mg | 1 mg | 2 mg |
50 units | 0.5 mg | 1.25 mg | 2.5 mg |
How many mg is 20 units of semaglutide?
At 2.5 mg/mL, 20 units is 0.5 mg, the second step in the standard schedule. At 1 mg/mL it's 0.2 mg, and at 5 mg/mL it's 1 mg.
How many mg is 40 units of semaglutide?
At 2.5 mg/mL, 40 units is 1 mg. At 1 mg/mL it's 0.4 mg, and at 5 mg/mL it's 2 mg.
How many mg is 50 units of semaglutide?
At 2.5 mg/mL, 50 units is 1.25 mg. At 1 mg/mL it's 0.5 mg, and at 5 mg/mL it's 2.5 mg. Notice how much the dose changes with concentration: the same 50 units can be five times more medication from one vial than another.
Semaglutide mg to units: every standard dose
Semaglutide mg to units on a U-100 syringe
Dose | 1 mg/mL | 2.5 mg/mL | 5 mg/mL |
|---|---|---|---|
0.25 mg | 25 units | 10 units | 5 units |
0.5 mg | 50 units | 20 units | 10 units |
1 mg | 100 units | 40 units | 20 units |
1.7 mg | 170 units* | 68 units | 34 units |
2.4 mg | 240 units* | 96 units | 48 units |
*More than one 100-unit syringe.
For the week-by-week schedule these doses follow, see the semaglutide dosage chart.
How to read your vial label
Your vial label shows two different numbers, and mixing them up is the most common cause of dosing mistakes:
Concentration is how much semaglutide is in each mL of liquid, for example 2.5 mg/mL. It describes the vial and stays the same for the whole vial.
Your dose is how much semaglutide you take each week, for example 0.5 mg. It comes from your prescription and changes as your provider adjusts it.
If your pharmacy changes, check the concentration again. A new vial can have a different concentration, which changes how many units you draw for the same dose.
What your medication should look like: a reddish color means your vial contains the B12 additive, and a clear liquid means it does not. Both are normal. If the liquid is cloudy, has particles, or doesn't match your prescription, stop and contact support.
How to read your syringe
U-100 insulin syringes come in three common sizes, and their markings differ:
U-100 insulin syringe sizes
Syringe size | Holds up to | Each small line |
|---|---|---|
0.3 mL | 30 units | 1 unit (some show half units) |
0.5 mL | 50 units | 1 unit |
1 mL | 100 units | 2 units |
Check which syringe you have before you draw, because the same mark can mean a different number of units on a different size.
Measure carefully. A small misreading can cause a large dosing error. FDA has received reports of patients drawing 50 units instead of 5. If you are unsure, ask your provider or pharmacist before injecting.
Do Wegovy and Ozempic pens use units?
No. Branded pens are set by dose in mg, not units, so there's nothing to convert. Units only matter when you draw a dose from a multi-dose vial, which is how compounded semaglutide is usually supplied.
Handling your vial
Use a new needle and syringe for every dose. Discard the vial by the date from your pharmacy or 28 days after first use, whichever comes first. If your medication arrives warm, contact the pharmacy or support before using it.
If you take too much
Extra medication most often causes mild stomach side effects. If nausea, vomiting or abdominal discomfort keeps getting worse, go to urgent care because this can be pancreatitis. Never double up on doses. If you believe you took more than prescribed, contact your healthcare provider promptly. You may also contact Poison Control at 1-800-222-1222. For severe or life-threatening symptoms, call 911 or seek emergency medical attention.
Semaglutide at NativeMed
At NativeMed, a licensed U.S. provider reviews your health history and decides whether compounded semaglutide is appropriate for you. Before treatment, you'll be asked to give your consent to treatment with a compounded medication. If it's prescribed, your label shows your vial's concentration and your dose, and your care team can help if anything is unclear.
Plans start from $149 a month, at the same price for any dose. See compounded semaglutide plans.
Compounded medications are not approved by the FDA, and the FDA does not review them for safety, effectiveness or quality before they are dispensed. Individual results vary. Read the full Important Safety Information.
Frequently asked questions
How many mg is 50 units of semaglutide?
At 2.5 mg/mL, 50 units is 1.25 mg. At 1 mg/mL it is 0.5 mg, and at 5 mg/mL it is 2.5 mg.
How many mg is 20 units of semaglutide?
At 2.5 mg/mL, 20 units is 0.5 mg. At 1 mg/mL it is 0.2 mg, and at 5 mg/mL it is 1 mg.
How many mg is 40 units of semaglutide?
At 2.5 mg/mL, 40 units is 1 mg. At 1 mg/mL it is 0.4 mg, and at 5 mg/mL it is 2 mg.
How many units is 0.25 mg of semaglutide?
At 2.5 mg/mL, 0.25 mg is 10 units. At 1 mg/mL it is 25 units, and at 5 mg/mL it is 5 units.
What size syringe should I use for semaglutide?
Use the U-100 insulin syringe your pharmacy or provider recommends. A 0.3 mL or 0.5 mL syringe makes small doses easier to measure, because each line is 1 unit instead of 2.
Sources
Medically reviewed by
Dr. Michael Wasef, MD
Board-Certified Internal Medicine Physician