At a glance
| Concentration | 1 mg is | Mark on U-100, 1 mL |
|---|---|---|
| 1 mg/mL | 1 mL | 100 |
| 2 mg/mL | 0.5 mL | 50 |
| 2.5 mg/mL | 0.4 mL | 40 |
| 5 mg/mL | 0.2 mL | 20 |
| 10 mg/mL | 0.1 mL | 10 |
Arithmetic at the concentrations shown. The concentration on your own label is the one that counts; enter it in the calculator.
Why the answer depends on the label
The Ozempic and Wegovy labels list strengths including 0.25, 0.5, 1, 1.7 and 2.4 mg, but those are delivered by pens that measure the dose for you. A vial of semaglutide drawn with an insulin syringe is a compounded preparation, which the FDA has not reviewed, and its concentration is set by the pharmacy. So the answer to this question is a formula, not a number. Millilitres equals milligrams divided by mg/mL. Units on a U-100 syringe equals millilitres times 100. For a 1 mg dose at 2.5 mg/mL that is 0.4 mL, the 40 mark. At 1 mg/mL it is a full 1 mL syringe, the 100 mark, and any dose above 1 mg at that concentration will not fit a 1 mL insulin syringe at all. Check which syringe you were given. The 0.5 mL and 0.3 mL syringes use the same scale but stop at 50 and 30 units. The calculator below performs this arithmetic with the concentration from your own label, and shows the intermediate volume so you can check it against your pharmacy's instructions.
The mistake to watch for. A label that says "5 mg vial" is not the same as "5 mg/mL". The first is the amount in the whole vial; the concentration is that amount divided by the fill volume. If your label shows only a vial amount and a volume, divide first.