What is the same
Same maker, both GLP-1 receptor agonists injected under the skin, both labelled for weight reduction with diet and activity, and both carry a boxed warning about thyroid C-cell tumors [1][2].
What differs
- Ingredient and rhythm: liraglutide once a day versus semaglutide once a week.
- Children: the Saxenda® US label covers children 12 and older who weigh more than 60 kg; in the EU, Saxenda® is also authorised for children aged 6 to under 12 who weigh at least 45 kg [1][4].
- Pens: Saxenda® is one multi-dose pen dialled to each step; Wegovy® comes mostly as single-dose pens of fixed strengths.
- Stopping rule: the Saxenda® label says to stop in adults if at least 4% of starting weight is not lost by week 16; the EU label uses 5% at 12 weeks on the maintenance dose [1][4].
Side by side, from the labels
| Label item | Saxenda® (injection) | Wegovy® (injection) |
|---|---|---|
| Active ingredient | Liraglutide, a GLP-1 receptor agonist | Semaglutide, a GLP-1 receptor agonist |
| Maker | Novo Nordisk | Novo Nordisk |
| FDA-approved uses | With diet and physical activity: long-term weight reduction in adults with obesity, or overweight plus a weight-related condition, and in children 12 and older with obesity who weigh more than 60 kg. [1] | With diet and physical activity: lowering the risk of major cardiovascular events in adults with cardiovascular disease and obesity or overweight; long-term weight reduction in adults and children 12 and older with obesity, and in adults with overweight plus a weight-related condition; MASH with moderate to advanced liver fibrosis in adults (accelerated approval). [2] |
| How it is taken | Once a day, under the skin of the abdomen, thigh or upper arm, at any time of day. | Once a week, under the skin of the abdomen, thigh or upper arm. The same label also covers Wegovy® tablets, taken once a day. |
| Forms in the US | A multi-dose 3 mL pen that delivers each step of the schedule; packs of 3 or 5 pens (section 3). | Single-dose pens (one strength sold as Wegovy® HD), single-dose syringes and the FlexTouch® multi-dose pen (section 3). |
| Dose steps | Section 2.2 of the label: a low daily dose raised every week up to a maintenance dose. In adults it says to stop if at least 4% of starting weight has not been lost by week 16. Doses not repeated here. [1] | Section 2.2 of the label: a low starting dose raised every 4 weeks, then a maintenance dose that depends on the use. Not repeated here; your prescriber sets your steps. [2] |
| Half-life (section 12.3) | About 13 hours [1] | About 1 week [2] |
| Most common side effects (label) | Nausea, diarrhea, constipation, vomiting, injection-site reactions, headache, low blood sugar, indigestion, fatigue, dizziness, abdominal pain and others listed in the label. | Nausea, diarrhea, vomiting, constipation, abdominal pain, headache, fatigue, indigestion, dizziness and others listed in the label. |
| Storage (label) | Refrigerated (2–8 °C) before first use. After first use up to 30 days at 15–30 °C or in the fridge. Not to be frozen. | Refrigerated (2–8 °C). A single-dose pen may be kept at 8–30 °C for up to 28 days; a FlexTouch® pen for up to 56 days after first use. Not to be frozen. |
| Boxed warning | Yes: risk of thyroid C-cell tumors. | Yes: risk of thyroid C-cell tumors. |
| In the EU (EMA) | Authorised since 2015; in the EU also for children aged 6 to under 12 who weigh at least 45 kg. [4] | Authorised since 2022 for weight management in adults and in adolescents 12 and older who weigh more than 60 kg; tablets for adults only. [5] |
Timing facts from the labels
| Label item | Saxenda® (injection) | Wegovy® (injection) |
|---|---|---|
| Half-life (section 12.3) | About 13 hours [1] | About 1 week [2] |
| Time to peak level (section 12.3) | About 11 hours after a dose [1] | 1 to 3 days after an injection [2] |
| Steady state (section 12.3) | The label gives steady-state levels, not a time to reach them [1] | The label gives steady-state levels, not a time to reach them [2] |
| After the last dose (section 12.3) | Not stated in the label [1] | About 5 to 7 weeks in the circulation after the last dose [2] |
| Missed dose (section 2) | Resumed with the next scheduled dose; after more than 3 days the label restarts the schedule from its first step (section 2.1) [1] | Given if the next dose is more than 2 days away, otherwise skipped (section 2.4) [2] |
| Section on switching | None [1] | Section 2.5, between Wegovy® injection and Wegovy® tablets only [2] |
Using them together
The Saxenda® label says combining it with other liraglutide products or any other GLP-1 receptor agonist is not recommended [1]. The Wegovy® label says the same for semaglutide products and any other GLP-1 receptor agonist [2].
Moving between them, in either direction
Neither the Saxenda® (injection) label nor the Wegovy® (injection) label sets out a schedule for moving from one to the other [1][2]. The timing facts above describe each medicine on its own; they are not a plan for a change. If a switch comes up, in whichever direction, the gap, the first dose of the new medicine and its steps are set by your prescriber.
Ozempic®, Wegovy®, Rybelsus®, Saxenda®, Victoza® and FlexTouch® are registered trademarks of Novo Nordisk A/S. Mounjaro®, Zepbound® and KwikPen® are registered trademarks owned or licensed by Eli Lilly and Company; Foundayo™ is a trademark of Eli Lilly and Company. PepLabo is not affiliated with or endorsed by these companies.
