GLP-1: therapeutic revolution or excessive hype? Current facts and issues

What is GLP-1? From the laboratory to the patient: mechanisms and promises

GlP-1 agonists (aGLP-1) today embody a decisive medical advance: they act at the interface of weight control and glycemic balance, relying on the incretin effect, the essential hormonal signal that regulates our energy balance. These molecules can now be found in the daily lives of many patients, even though their development began in the laboratories of Novo Nordisk or Eli Lilly, and then in an endocrinology department – a not so linear path, between research, testing and clinical caution. The very first analog, inspired by the venom of a desert lizard, paved the way for a new approach to the management of type 2 diabetes and overweight patients resistant to conventional approaches. Today, they are asked to combine two ambitions: to control the increase in body fat and to stabilize blood sugar levels, sometimes when no hygienic-dietary measures have made any headway.

Generics are still absent, but the segment’s flagship drugs remain well identified:

• Ozempic (semaglutide)

• Wegovy (semaglutide, anti-obesity component)

• Victoza (liraglutide)

Saxenda (liraglutide, focused on weight reduction)

• Mounjaro (tirzepatide)

• Trulicity (dulaglutide)

• Exenatide, the pioneer – some diabetologists remember the early trials

The incretin-like effects of Exenatide include increased insulin secretion, reduced glucagon levels, slower gastric transit and an impressive appetite-suppressant effect. As a result, appetite is frequently reduced, leading to significant weight reduction in many patients, sometimes in just a few months. But not everyone reacts in exactly the same way – as endocrinologists repeat: tolerance and efficacy vary, and some experience more moderate weight loss, or digestive side effects.

The management of type 2 diabetes, long centered on the classic arsenal (various tablets, insulin), is now benefiting from this new therapeutic family, to the point where comparison with bariatric surgery is invited into congress discussions, even if, in real life, endocrinologists and diabetologists temper the enthusiasm. Tirzepatide, the latest addition, combines GIP and GLP-1 action in a formulation that intrigues the medical community; but caution remains the order of the day, in the absence of hindsight on certain very rare effects or the optimal duration of the protocol.

Notable fact: we are witnessing a proliferation of alternative products, such as GLP-1 patches touted online by health influencers. No dermal device has demonstrated the slightest benefit in serious studies – and pharmacists warn of the risks of confusion or counterfeiting, particularly when the official logo or packaging appears genuine. This is where patient associations and health insurance groups, sometimes backed by public campaigns, issue messages of vigilance.

Pharmaceutical companies such as Novo Nordisk or Eli Lilly dominate this sector, with exclusively medical prescriptions (no over-the-counter deliveries), combined with compulsory hygiene and diet support. In France, since 2025, general practitioners and endocrinologists have been able to prescribe certain molecules for broader indications – a turning point that has also led to tighter monitoring. Patients, for their part, are encouraged never to start these treatments without a full assessment, as the best alliance remains that of doctor-patient dialogue.

Consult your healthcare professional to take stock of the options best suited to your situation.

Main mechanisms and players in aGLP-1:

• Insulin stimulation, glucagon inhibition

• Enhanced satiety, reduced intake, which may have surprised many patients during the very first month of injection

• Administration by subcutaneous injection, weekly or daily

• Indications: type 2 diabetes, proven obesity (BMI ≥30 or ≥27 with recognized comorbidities, such as hypertension or sleep apnea)

• Need for rigorous medical follow-up

Effectiveness data and real benefits: what recent studies and medical recommendations show

GLP-1 analogues benefit from a consistent set of international clinical trials; these question their potential on weight loss, cardio-metabolic improvement or tolerance over time. The context has nothing to do with mere advertising: efficacy is attested by randomized, often multicenter studies.

The major studies, the results of which some patients are still following via their healthcare team:

• LEADER (liraglutide): lower cardiovascular incidence in diabetics

• SUSTAIN-6 (semaglutide): metabolic effects, reduced risk of stroke

• SELECT (semaglutide, obese population): average weight loss of around 15%, improvement in risk factors

• SURMOUNT-1 (tirzepatide): loss of up to 22% in obese patients, generating strong demand, up to acute shortages reported in pharmacies

• SURPASS-2 (tirzepatide vs. semaglutide): demonstrated superiority of dual GIP/GLP-1 agonist

The cross-over analysis of these trials clearly highlights:

• Decreases in weight of 8 to 22%, depending on the molecule, the profiles, and therapeutic compliance – sometimes less, sometimes much more, no one is strictly “average” every time

• A tangible impact on glycemia, but also lipid or blood pressure balances in well-targeted patients

• Encouraging signals for cardiovascular risk, but the benefit on all-cause mortality remains, to date, an issue under scrutiny (many experts call for caution on this point)

• Well-being reported in patients followed up, with a lasting effect under treatment, but the body’s metabolic memory may disrupt the maintenance of long-term results

Regulatory authorities, including ANSM, FDA, Swissmedic, HMA or BfArM, confirm the clinical benefit, while insisting on the need for reinforced medical monitoring and strict prescription registration. In hospital practice, biological monitoring is often adapted on a “case-by-case” basis, depending on the patient’s history and digestive tolerance. Newly involved general practitioners are encouraged to dialogue with diabetologists or nutritionists to avoid any drift towards purely cosmetic use – the distinction is essential for public health.

In France, renowned specialists such as Jean-Pierre Riveline or Judith Aron-Wisniewsky remind us of the importance of nutritional monitoring and respect for clinical indications. And in some centers, a multidisciplinary team meets regularly to adjust or stop treatment: the question of optimal duration is often debated.

Ask your doctor for advice on the relevance of study data to your situation.

Comparative table of GLP-1 molecule efficacy

Our point of view: between concrete progress and citizen caution

The growing interest in aGLP-1 is part of a dynamic of progress in the management of overweight and diabetes, with real social pressure around thinness, which patient associations and treating physicians regularly report. However, marketing promises and the rhetoric of certain health influencers need to be kept in perspective, even if media coverage is omnipresent.

A reasoned clinical approach distinguishes proven innovation – controlled, weighed and nuanced – from the illusion often fostered by excessive communication or expectation. The medicalization of overweight may prove necessary in cases of therapeutic deadlock (as many endocrinologists confirm), but it must never replace prevention or mask social issues: stress, physical activity and sleep remain fundamental levers for patients.

Somewhere, the multiplication of offers and digital marketing are fuelling rampant misinformation, to the point where some laboratories are calling for pharmaceutical advertising to be regulated and prescribers to be made more responsible. The question of prescribing ethics, much discussed in medical debates, is linked to that of collective responsibility, particularly with regard to young people or people looking for quick solutions.

At the present time, it is essential to combine scientific innovation, medical supervision and diplomacy between all players – laboratories, doctors, pharmacists and patients – to safeguard the relevance of a reasoned use of these treatments and avoid over-medicalization. This vigilance is all the more necessary given that the body’s metabolic memory and the psychological constraints associated with weight loss are clearly not the same for everyone.

Risks, side effects and limits: attention to treatment safety and medical follow-up

Behind the potential of GLP-1 agonists lie a whole host of adverse effects and constraints, the repercussions of which patients, GPs and pharmacists sometimes have to deal with on a daily basis.

Main side effects observed:

• Nausea

• Vomiting

• Digestive disorders: diarrhea or constipation

• Abdominal pain

In consultation, some patients report episodes of fatigue or discomfort, sometimes underestimated during initial follow-up. More rarely, a few complications noted:

• Acute pancreatitis (rare risk, but described and sometimes monitored by specific biology)

• Gallbladder problems (stones or inflammation, to be monitored especially in at-risk subjects)

• Hypoglycemia (mainly in association with sulfonamides, requiring careful adjustments in complex diabetics)

It’s not uncommon for a yoyo effect to occur after treatment has been stopped – the rapid regaining of weight or the resurgence of metabolic memory raises questions about the ideal protocol. At follow-up meetings, diabetologists often discuss the transition modalities and the reinforced monitoring to be planned over several months. The duration of treatment remains a matter of debate, in the absence of a solid consensus on the optimal period.

The question of cost is far from secondary: up to €400 per month outside reimbursement, a major brake for patients not covered, especially when the indication is close to cosmetic. Health insurance groups and regulators – with the help of pharmacists – recall the distinction between validated medical indications and cosmetic uses, the latter being exclusively excluded from any reimbursement. Medical prescription, close monitoring, regular biological controls: it’s best not to trivialize these treatments.

Stay vigilant and promptly report any adverse effects to a healthcare professional.

Table: main risks and constraints of aGLP-1

Scams and misuse: beware the boom in counterfeits and illegal marketing

The success of GLP-1 agonists is accompanied by an explosion in online sales and counterfeits, to the point where some patients themselves are offered “solutions” in groups on social networks, without the slightest guarantee of safety. Fake substances can be found, sometimes mislabeled insulin, or patches whose medical efficacy has never been established – several pharmacists report having been solicited “unbelievably” for supposedly miraculous products.

French, European and Swiss legislation imposes a mandatory prescription; dispensing can only take place in pharmacies under supervision. Any derogation exposes the patient to serious risks: hypoglycemic accidents, allergic reactions, even emergency hospitalizations are mentioned by patient associations or reported in the medical press – NEJM, The Lancet or Marc Gozlan have already taken up the subject.

Don’t start any treatment without your doctor’s advice, and report any suspicious advertising or dubious practices to your pharmacist or health authorities.

Risks to note in particular:

• Sale of uncertified “weight-loss” products on the internet

• Usurpation of official logos or regulatory aspects on certain sites (influencers can sometimes relay without verification)

• Risk of confusion with insulin, potential severe hypoglycemic accident

• Promotion of cosmetic devices or patches without proof of serious medical efficacy

• Dissemination of misleading information, sometimes amplified by the viral effect of social networks – patient associations here have already launched prevention campaigns

Societal, ethical and economic issues: striking a balance between medical progress, equitable access and prevention of abuses

The rise of GLP-1 – and the forthcoming opening of prescriptions to general practitioners (since June 2025 in France) – invites us to think beyond strict efficacy, integrating the sensitive issue of equitable access and social responsibility. Patients from different backgrounds do not benefit from the same access everywhere, as laboratories and health insurance groups face the headache of reimbursement and the actual price in practice. Pharmacists and associations insist: the risk of excessive medicalization, driven by social pressure on weight and relayed by digital marketing, is clearly not a mere detail.

Here we touch on market regulation and advertising control: pharmacovigilance monitoring, investigations into illegal practices or campaigns to arrest after fraud, are an integral part of current health surveillance. Prescribing ethics, public health, body acceptance, misinformation or the benefit/risk ratio: all converge towards the need for accurate, balanced and critical information.

There remains the need to distinguish between progress and excessive promise. Informing without stigmatizing, promoting responsible use of innovations, preventing marketing abuses – these are the demands of patient associations, healthcare professionals and industry experts. Personalized support, combining validated care, discussion with the doctor and awareness of prevention, remains the cornerstone of responsible use.

Get your information exclusively from recognized sources, and talk to your healthcare team to ensure that GLP-1 is appropriate for you.