Two brands of the same molecule, two completely different delivery designs. Ozempic uses a multi-dose pen you dial; Wegovy uses a single-dose pen you use once and discard. Knowing which you hold answers most practical questions before they come up.
Ozempic: dial a dose from a multi-dose pen
The Ozempic label lists three prefilled pens, each 3 mL, each for one patient:
| Total per pen | Concentration | Doses per pen |
|---|---|---|
| 2 mg in 3 mL | 0.68 mg/mL | Four 0.25 mg doses and two 0.5 mg doses (initiation), or four 0.5 mg doses |
| 4 mg in 3 mL | 1.34 mg/mL | Four 1 mg doses |
| 8 mg in 3 mL | 2.68 mg/mL | Four 2 mg doses |
The dose counter shows milligrams. The pen is engineered so that the marked dose is what comes out; the concentration is only there to explain why the three pens differ. A 2 mg per 1.5 mL strength exists on the label but is not currently marketed. Each carton includes NovoFine Plus needles, and a new needle is used for every injection.
Storage: refrigerated at 2°C to 8°C (36°F to 46°F) before first use. After first use, the pen can be kept for 56 days at room temperature (15°C to 30°C, 59°F to 86°F) or in the refrigerator. Do not freeze, and do not use a pen that has been frozen. Protect from light and keep the cap on.
Wegovy: one pen, one dose
Wegovy's single-dose pens each hold exactly one injection, with an integrated needle, four to a carton:
| Pen | Volume | Concentration |
|---|---|---|
| 0.25 mg | 0.5 mL | 0.5 mg/mL |
| 0.5 mg | 0.5 mL | 1 mg/mL |
| 1 mg | 0.5 mL | 2 mg/mL |
| 1.7 mg | 0.75 mL | 2.27 mg/mL |
| 2.4 mg | 0.75 mL | 3.2 mg/mL |
| 7.2 mg (Wegovy HD) | 0.75 mL | 9.6 mg/mL |
Every strength is a different concentration. There is no dial and no dose counter: you press, hold and discard. Each step of the escalation schedule is a different carton, which is why the titration planner marks the date each new step begins.
Storage: refrigerated at 2°C to 8°C. If needed, before the cap is removed, a pen can be kept at 8°C to 30°C (46°F to 86°F) for up to 28 days. Do not freeze, protect from light, and keep the pen in its carton until use.
Why none of this is in units
Insulin syringes are marked in U-100 units, 100 to the millilitre. That is a volume scale for drawing from a vial. Neither Ozempic nor Wegovy involves a vial or a syringe you fill yourself, so "how many units" has no answer for them. The question only arises with compounded semaglutide, dispensed in a vial with a concentration on its label, and there the answer changes with every concentration. The units converter is built for that case and only that case. Compounded semaglutide is not FDA approved and is not interchangeable with either brand pen.
Injection technique, per the labels
Abdomen, thigh or upper arm, rotating sites within a region. Any time of day, with or without food, on the same day each week. If you also inject insulin, the labels say to use separate injections, never mix, and not to inject adjacent to each other. Inspect the solution: clear and colourless, or do not use it.
Travel and temperature
The 28-day (Wegovy, before cap removal) and 56-day (Ozempic, after first use) room-temperature allowances are what make travel feasible without a cooler for most trips. Both upper limits are 30°C (86°F); a car in summer exceeds that quickly. The FormBlends Tools site has a printable travel checklist for pens and vials.
Questions people ask
Why does my Ozempic pen have a different colour label from my friend's?
Because it is a different strength. The three pens hold different concentrations so that four clicks of the dial deliver 0.25 or 0.5 mg, 1 mg, or 2 mg. The dose counter reads in mg, not units.
Can I share a pen if we each use a new needle?
No. Both labels say a pen must never be shared between patients, even if the needle is changed.
How many units is a Wegovy 2.4 mg pen?
The question does not apply. A Wegovy pen delivers its whole content as one dose; there is nothing to measure. Syringe units only matter for a vial with a stated concentration.
Sources
- Ozempic (semaglutide) injection prescribing information, revised 1/2025, section 16, Drugs@FDA Accessed September 4, 2026.
- Wegovy (semaglutide) injection and tablets prescribing information, revised 6/2026, sections 3 and 16, DailyMed Accessed September 4, 2026.
Canonical URL: https://formblendssemaglutide.com/guides/semaglutide-pens-explained. Written by the FormBlends editorial team. This page is educational and is not medical advice; see the medical disclaimer.