Anti-obesity medications: treatments, indications and management

Anti-obesity medications: Wegovy, Mounjaro, Saxenda and available treatments

In the fight against obesity, 4 main classes of anti-obesity medications form the basis of the therapeutic arsenal:

  1.  Lipid absorption inhibitors;

  2.  GLP-1 agonists;

  3.  GIP and GLP-1 receptor co-agonists;

  4.  New hormonal pathways (currently in development).

Two other treatments may be added to these four main approaches: the naltrexone/bupropion combination (Mysimba) and the MC4R agonist setmelanotide (Imcivree).

Anti-obesity medication: lipid absorption inhibitors (orlistat, Xenical)

Belonging to the pharmaceutical class of lipid inhibitors, orlistat is an anti-obesity medication that inhibits pancreatic lipase, reducing the absorption of dietary triglycerides by around 30%. Orlistat is marketed under the brand names Xenical (prescription only) and Alli (over the counter). According to current data, it can lead to weight loss of 3% over one year. However, its effectiveness is often limited by gastrointestinal side effects (flatulence, steatorrhoea).

GLP-1 receptor agonists: Wegovy, Saxenda and Ozempic

GLP-1 analogues act on both insulin secretion and satiety. For example, liraglutide, marketed under the brand name Saxenda (3 mg/day), can produce a loss of 8 to 10% of initial body weight over 56 to 72 weeks. The main side effect reported is nausea, most often transient. Finally, semaglutide, marketed under the name Wegovy (2.4 mg) or Ozempic (for diabetes treatment), can produce a loss of 14.9% of body weight over 68 weeks, and up to 15.2% at 104 weeks (STEP trials). A weekly semaglutide injection is required, with a gradual dose escalation.

GLP-1/GIP co-agonists for weight loss

Tirzepatide is the first GLP-1 and GIP receptor co-agonist. It works by promoting satiety and lipolysis. Marketed under the brand names Mounjaro and Zepbound, it produced an average weight loss of 21.3% over 72 weeks, according to data from the SURMOUNT-1 trial. To get a prescription for an appropriate treatment, easily consult a general practitioner with Feeli, available in under 2 hours.

Specific combinations and targeted treatments

In addition to the anti-obesity treatments mentioned above, two medications with specific mechanisms are now authorised in Europe:

  •  Naltrexone/bupropion (Mysimba): authorised by the EMA in March 2015 for obesity (BMI ≥ 30 kg/m² or ≥ 27 kg/m² with comorbidities), this oral combination pairs an opioid receptor antagonist (naltrexone) with a noradrenaline/dopamine reuptake inhibitor (bupropion). It helps regulate appetite and the food reward system. The estimated weight loss is ≥ 5% of initial body weight in around 28 to 42% of patients after 56 weeks.

  •  Setmelanotide (Imcivree): this is a selective MC4R receptor agonist, authorised in the European Union since July 2021 for patients with monogenic obesity (a hereditary condition linked to a gene alteration). In patients with Bardet-Biedl syndrome, a phase III trial produced a loss of ≥ 10% of initial body weight in 46.7% of patients at 52 weeks. Hunger scores also showed a notable improvement.

Which anti-obesity medication should you choose? Effectiveness, price and reimbursement

Here is a detailed overview of the various anti-obesity medications.

Orlistat (Xenical / Alli): mechanism of action and effectiveness

By binding to the active site of enzymes, orlistat (Xenical) blocks up to 30% of the hydrolysis of dietary triglycerides. This helps reduce energy intake by around 200 to 300 calories per day. Meta-analyses have shown an additional average weight loss of 2.9% compared with dietary measures alone (and up to 5% in 1-year studies). Regarding dosage, the HAS (French National Authority for Health) recommends one 120 mg capsule with each main meal (before, during or within the hour that follows), and stopping at 12 weeks if weight loss is less than 5% of initial body weight. In all cases, the treatment must be combined with a calorie-reduced diet and regular physical activity, in line with EMA (European Medicines Agency) recommendations. In addition, Xenical (orlistat 120 mg) is not reimbursed in France and its price generally ranges from €40 to €80 for a box of 84 capsules. This price is freely set by pharmacies. As for its other version, Alli (orlistat 60 mg), available over the counter in other European countries, it is no longer marketed in France. For more information or a diagnosis, easily consult a doctor by teleconsultation.

Liraglutide (Saxenda): results, price and coverage

Liraglutide is a GLP-1 analogue designed to extend its half-life. Its 3 mg/day dosage slows gastric emptying and also acts on the feeling of satiety. In the SCALE Obesity and Prediabetes study, 63.3% of patients on liraglutide lost around 5% of their starting weight, with an average reduction of 8% at 56 weeks. The results showed an average reduction of –8 kg. According to data provided by the ANSM (French medicines agency), the monthly cost of Saxenda generally ranges between €240 and €300 and it is not reimbursed by the French health insurance. Initially reserved for specialists, its prescription is now open to all doctors, just like Wegovy.

Wegovy and Ozempic: indications, effectiveness and reimbursement

Semaglutide is a GLP-1 (glucagon-like peptide-1) receptor agonist that acts centrally and digestively by increasing satiety, reducing appetite and slowing gastric emptying, which helps reduce food intake. Notably marketed under the brand name Wegovy (semaglutide 2.4 mg), it is indicated for the management of overweight and obesity, always alongside a calorie-reduced diet and regular physical activity (BMI ≥ 35 kg/m² with failure of a well-conducted nutritional approach (<5% at 6 months), or BMI ≥ 40 kg/m²). Regarding its effectiveness, the STEP-1 trial showed an average weight loss of around 14.9% at 68 weeks, making it a potentially effective medication. Wegovy is available on prescription only. Ozempic does not have a marketing authorisation for obesity, but it can lead to weight loss and may be the subject of supervised off-label prescriptions. It is initially indicated for the treatment of type 2 diabetes. Cost and reimbursement in France: the average pharmacy price of Wegovy is around €146.91 to €195.10 per month depending on the dose (excluding dispensing fee). From 15 June 2026, Wegovy will be reimbursed at 65% by the French health insurance (Assurance Maladie) under strict conditions of severe obesity:

  •  BMI ≥ 40 without comorbidity;

  •  Or BMI ≥ 35 with comorbidity.

This reimbursement by the Assurance Maladie considerably reduces the out-of-pocket cost, which is often supplemented by complementary health insurance (mutuelle). Ozempic is only reimbursed in the context of type 2 diabetes.

Anti-obesity medication: Tirzepatide (Mounjaro / Zepbound)

Tirzepatide is a dual GIP and GLP-1 receptor agonist. It helps reduce food intake by acting centrally and digestively: increasing satiety, reducing appetite and slowing gastric emptying. In Europe, tirzepatide is marketed under the brand name Mounjaro. It has a marketing authorisation for the treatment of type 2 diabetes. It is also indicated for weight management in overweight or obese adults, in combination with a calorie-reduced diet and regular physical activity. Regarding its effectiveness, the SURMOUNT-1 phase III clinical trials showed an average weight loss of around 20.9% at 72 weeks, combined with dietary and lifestyle measures. In France, Mounjaro is available on prescription only. It is covered by the Assurance Maladie for the treatment of type 2 diabetes, according to the prescribing and reimbursement conditions set by the health authorities. From 15 June 2026 in France, Mounjaro will also be reimbursed by the Assurance Maladie at a rate of 65%, as part of a structured care pathway after a well-conducted nutritional approach has failed. This coverage applies to patients with:

  •  a BMI ≥ 40 kg/m² without comorbidity,

  •  or a BMI ≥ 35 kg/m² with at least one associated comorbidity.

Finally, for the treatment of obesity, Mounjaro must always be prescribed as a second-line treatment, after a well-conducted nutritional approach has failed. Medical follow-up is essential.

Which patients can benefit from anti-obesity treatment in France?

The Haute Autorité de Santé (HAS, French National Authority for Health) has issued several recommendations to structure the care pathway for overweight or obese adults. These recommendations aim to standardise medical care and optimise treatment effectiveness. To be eligible for an anti-obesity medication, the HAS recommends:

  1.  Initial screening and assessment:

    • Every patient should undergo systematic screening for overweight (BMI ≥ 25 kg/m²) and obesity (BMI ≥ 30 kg/m²) before being prescribed a GLP-1 analogue.

    • Blood tests are recommended, particularly if the overweight or obesity is associated with comorbidities (hypertension, diabetes, dyslipidaemia).

  2.  Eligibility criteria for drug treatments:

    • Pharmacological treatments for obesity are reserved for patients with a BMI ≥ 30 kg/m², or ≥ 27 kg/m² in the presence of significant comorbidities.

    • Before any prescription, patients must have undergone non-drug support (regular physical activity, calorie-reduced diet, psychological support) judged insufficient after at least 6 to 12 months.

  3.  Assessment of the medical benefit (SMR):

    • The medical benefit rendered (SMR) must be assessed (the therapeutic value of the treatment). The HAS analyses the clinical value and its place in the decision-making pathway (for example, an unfavourable opinion on reimbursing Wegovy for a BMI below 35 kg/m² without severe comorbidities).

ANSM safety measures

The Agence nationale de sécurité du médicament et des produits de santé (ANSM, French medicines safety agency) has put in place a monitoring and oversight framework specific to anti-obesity medications:

  1.  Initial prescription:

    • Since 23 June 2025, the initial prescription of Saxenda, Wegovy and Mounjaro is no longer reserved for specialists; all doctors, including GPs, can now initiate these treatments, in accordance with their marketing authorisation.

  2.  Renewal:

    • Any doctor can renew an anti-obesity treatment, subject to regular follow-up.

  3.  Monitoring of side effects and proper use:

    • Serious side effects and misuse (aesthetic prescriptions outside the marketing authorisation's indications) can be reported to the ANSM via the CRPV network and EpiPhare. It is also crucial to follow the injection procedures and dose escalation.

To find out if you are eligible for anti-obesity treatments, easily consult a doctor without an appointment with Feeli, available in under 2 hours.

Frequently asked questions (FAQ) about anti-obesity medications