Beware of deficiencies, misuse and other risks induced by glucagon-like-peptide-1 (α-GLP-1) receptor analogues, new treatments for diabetes and obesity. Because if the conclusion of the latest national pharmacovigilance survey conducted from summer 2023 to winter 2025 by the National Agency for the Safety of Medicines and Health Products (ANSM) confirms overall the safety profile of these drugs, as is often the case, the devil is in the details.
Gastrointestinal disorders: the most common side effects
THE report This concerns approximately 870,000 patients using the seven molecules currently reimbursed in France: Trulicity (dulaglutide), Victoza (liraglutide), Xultophy (liraglutide) and Ozempic (semaglutide) in the treatment of diabetes, Saxenda (liraglutide), Wegovy (semaglutide) from September 2024 and Mounjaro (tirzepatide) from November 2024 in the second-line treatment of obesity. Unsurprisingly, gastrointestinal disorders (nausea, vomiting, constipation, diarrhea) are the most frequently reported (48%), all of which usually cease when treatment is stopped or fade over time. But these mild side effects should not obscure others, which are rarer but much more severe.
“ During the period studied, from 1er From August 2023 to January 31, 2025, 376 serious cases were reported, 140 of which involved the use of GLP-1 receptor agonists (GLP-1 inhibitors) to treat obesity. Nineteen deaths were reported in patients treated with GLP-1 inhibitors, although a direct link to these medications could not be established., writes the ANSM. Reading the report also reveals other, less documented signs of adverse effects, which nevertheless require preventive measures or enhanced monitoring.
Example with a higher risk of thyroid cancer. This is a potential signal identified in a previous report, writes the ANSM. Two new meta-analyses of clinical trials published in 2025 reinforce the hypothesis of an increased risk with GLP-1 receptor agonists, which has not yet been confirmed by the PRAC. (THE (pharmacovigilance committee of the European Medicines Agency, editor's note). These results will be shared at the European level..
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Iron and vitamin deficiencies
Another recently identified indicator is iron and vitamin deficiencies. The quantitative and qualitative changes in dietary intake associated with GLP-1 receptor agonists can lead to serious deficiencies. These risks and their complications necessitate nutritional monitoring and appropriate supplementation of patients.health authorities specify.
Finally, regarding the risk of complications that may occur during surgical procedures in these patients, the rapporteurs propose that " "Clear recommendations for their perioperative management should be established in conjunction with the relevant learned societies.".
And the Agency finally reiterated in its conclusions that, on the one hand, serious cases linked to misuse are always preventable, specifying that, of the 36 cases of adverse effects reported in connection with this practice, which is also on the rise, 25 were serious. For example: » Three cases of acute pancreatitis occurred in young patients with no identifiable risk factors, one of whom was only moderately overweight.“.
The Agency also specifies that theThe adverse effects linked to misuse occurred in the absence of dose escalation (with a high dose taken initially) or in a context of unsupervised use. Of these 36 cases, 22 involved situations where the medication was obtained outside of official medical channels (via a relative, family member, or abroad), and 18 reported an excessively high initial dose. Caution is therefore advised.
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