Weight loss
Same molecule, different brand, different approval: the detail that decides everything
Two molecules dominate this category and each is sold under two names. Semaglutide is Wegovy when it is approved for weight and Ozempic when it is approved for type 2 diabetes. Tirzepatide is Zepbound for weight and Mounjaro for diabetes. Same substance, different label, different approved use.
That is not a marketing quirk. The approved indication decides what a doctor can prescribe it for, what a health system will pay, and which dose schedule the label sets. Every page here states which brand carries which approval before it states anything else.
Medicines
Weight loss
- SemaglutideWegovy, Ozempic, RybelsusOne substance under three brand names, and only one of those brands is approved for weight. Which name is on the box decides what it was approved to do.Prescription only
- TirzepatideZepbound, MounjaroThe newer injection, acting on two gut hormone receptors instead of one, and sold as Zepbound for weight and Mounjaro for diabetes.Prescription only
- LiraglutideSaxenda, VictozaThe first of these injections to be approved for weight, taken daily rather than weekly, and now the one with a generic on the way.Prescription only
- OrlistatXenical, AlliThe old option, a tablet that blocks the absorption of part of the fat in a meal, and the only one in this category sold without a prescription in Europe.Prescription only
- Naltrexone and bupropionMysimba, ContraveA tablet combining two older medicines, sold as Mysimba in Europe and Contrave in the United States, and the one in this category with the longest list of contraindications.Prescription only
Comparison
The two labels, side by side
- Ozempic and Wegovy: one substance, two approvalsThe two names describe the same active substance under two separate approvals, and the difference between them is not chemistry but what each was authorised to be used for and at what dose.
- Mounjaro and Ozempic, compared from both labelsTwo different substances, both injected weekly, both approved in the United States for type 2 diabetes under these brand names. The comparison people usually want is about weight, and that is where the labels stop being able to answer.
Written by us
How to get it legally
Every injectable in this category is prescription-only and every label sets entry conditions: a body mass index above a stated threshold, or above a lower threshold together with a weight-related condition. A prescriber who does not ask for height, weight and medical history is not following the label.
Orlistat is the exception. A lower-dose version is sold over the counter in the European Union and the United Kingdom under pharmacy supervision, which makes it the only option here that does not require a prescription at all.