Semaglutide: which line to draw to
Enter your Semaglutide vial amount, the water you added and your dose. Semaglutide is dosed in mg; the syringe shows exactly where to stop. New to this?
Your line shows up here.
Fill in the vial, water and dose boxes.
Approved drug. Sold as Ozempic and Wegovy.
Semaglutide at a glance
- Evidence
- Approved drug. Sold as Ozempic and Wegovy.
- Vial sizes
- 2, 3, 5, 10 mg
- Usual dose range
- 0.25–2.4 mg
- How often
- Weekly
- Unmixed
- Freezer −20°C
- After mixing
- Fridge 2–8°C, use within 28 days
Semaglutide units to mg chart
Syringe units on any U-100 insulin syringe (100 units = 1 mL), worked out by the same engine as the calculator. Your own vial and water may differ: use the calculator for your numbers.
| Dose | Units | mL |
|---|---|---|
| 0.25 mg | 12.5 | 0.125 |
| 0.5 mg | 25 | 0.25 |
| 1 mg | 50 | 0.5 |
| 1.7 mg | 85 | 0.85 |
| 2.4 mg | More than the vial holds | |
| Dose | Units | mL |
|---|---|---|
| 0.25 mg | 8.3 | 0.083 |
| 0.5 mg | 16.7 | 0.167 |
| 1 mg | 33.3 | 0.333 |
| 1.7 mg | 56.7 | 0.567 |
| 2.4 mg | 80 | 0.8 |
| Dose | Units | mL |
|---|---|---|
| 0.25 mg | 10 | 0.1 |
| 0.5 mg | 20 | 0.2 |
| 1 mg | 40 | 0.4 |
| 1.7 mg | 68 | 0.68 |
| 2.4 mg | 96 | 0.96 |
| Dose | Units | mL |
|---|---|---|
| 0.25 mg | 7.5 | 0.075 |
| 0.5 mg | 15 | 0.15 |
| 1 mg | 30 | 0.3 |
| 1.7 mg | 51 | 0.51 |
| 2.4 mg | 72 | 0.72 |
Semaglutide questions
How many units is 0.25 mg of Semaglutide?
With a 2 mg vial mixed with 1 mL of bacteriostatic water, 0.25 mg is 12.5 units (0.125 mL) on a U-100 insulin syringe. A different vial size or amount of water changes this, so check it with your own numbers.
How much water do I add to a 2 mg Semaglutide vial?
1 mL of bacteriostatic water is common, which makes 2 mg per mL. More water makes each dose a bigger amount that is easier to measure; it doesn't change how much is in the vial.
How long does mixed Semaglutide last?
Once mixed, keep it at fridge temperature, 2–8°C and use it within 28 days. Unmixed powder: freezer −20°c.
What is Semaglutide?
Semaglutide is a GLP-1 medicine, approved as Ozempic for type 2 diabetes and as Wegovy for weight management. It copies a gut hormone that reduces appetite and slows stomach emptying. In the main weight trial (STEP 1), people on 2.4 mg a week lost about 15% of their body weight on average over 68 weeks.
Mixing a vial
Pharmacy pens come ready to use. Vials of powder are mixed with bacteriostatic water: let it run down the inside wall of the vial, then swirl gently until it’s clear, without shaking. Don’t use it if it stays cloudy or has specks in it.
Some compounded vials come already mixed, with the strength on the label (for example 2.5 mg/mL). Those need no water.
Stepping up
The approved schedule starts at 0.25 mg once a week and steps up every 4 weeks to a 2.4 mg maintenance dose; the calculator shows the full schedule. Going up faster makes nausea and vomiting much more likely. Your prescriber may use a different pace, or stop at a lower dose.
What to watch for
Nausea, diarrhoea and constipation are common, especially after a dose goes up. Severe stomach pain that doesn’t go away can be pancreatitis and needs medical help the same day. The label also warns about gallbladder problems and thyroid tumours seen in rodents.
Sources
- Wilding JPH et al. Once-Weekly Semaglutide in Adults with Overweight or Obesity. N Engl J Med, 2021.
- Marso SP et al. Semaglutide and Cardiovascular Outcomes in Patients with Type 2 Diabetes. N Engl J Med, 2016.