On Wednesday, April 16, 2025, the Agência Nacional de Vigilância Sanitária (Anvisa) announced a significant regulatory change concerning the sale of weight-loss medications. The agency has mandated that medical prescriptions must be retained at the point of sale for drugs such as Ozempic, Wegovy, and Saxenda, which are commonly used for weight management and are also indicated for treating type 2 diabetes.
This decision was reached unanimously during a meeting of Anvisa's board of directors. The agency recognized that retaining prescriptions would enhance control over the use of these medications and help protect public health from what it termed "irrational consumption" of slimming drugs. Prior to this change, pharmacies were only required to check for a prescription at the time of purchase but could return the document to consumers.
Under the new rules, pharmacies will have to keep the prescription for these medications, similar to the regulations applied to antibiotics and other controlled substances. To be valid, prescriptions must be issued within the last 90 days and consist of two copies. Pharmacies will also be required to register these prescriptions in the Sistema Nacional de Gerenciamento de Produtos Controlados (SNGPC).
The new regulation will come into effect 60 days after its publication in the Diário Oficial da União, which is expected shortly. Anvisa's decision stems from concerns over a high number of adverse events related to the indiscriminate use of these medications, particularly among individuals using them solely for aesthetic purposes without medical supervision.
According to data presented during the meeting by Thamires Capello, a researcher at the Centro de Pesquisa em Direito Sanitário at USP, 45% of users of semaglutide or tirzepatide-based medications do not possess a medical prescription. Alarmingly, within this group, 73% reported never having received any professional guidance regarding their use. Furthermore, the survey indicated that 56% of users are using these drugs for weight loss, with 37% of them not classified as overweight or obese, highlighting a misuse of the medications.
Experts have raised concerns about the health implications of using weight-loss drugs without medical supervision. The potential side effects include nausea, abdominal distension, constipation, diarrhea, and even exacerbation of psychological and eating disorders. The Brazilian societies of Endocrinology and Metabolism and Diabetes have publicly supported the prescription retention policy, emphasizing the need for stricter control to protect public health.
In addition to the retention of prescriptions, Anvisa's new guidelines will include other GLP-1 agonist medications, such as liraglutide, dulaglutide, exenatide, tirzepatide, and lixisenatide. These drugs are designed to mimic the action of GLP-1, a hormone that regulates appetite and insulin release, making them effective for weight management.
The urgency of this regulatory change was underscored by the alarming statistics regarding adverse events associated with these medications. Reports indicate that 32% of notifications related to adverse events in Brazil stem from uses not listed in the product package inserts, a figure significantly higher than the international average of approximately 10%. Additionally, the incidence of pancreatitis linked to these drugs in Brazil is reported at 5.9%, compared to a global rate of 2.4%.
Renato Alencar Porto, a representative from Interfarma, highlighted the necessity of revising current regulations to address the misuse of these medications. He noted the concerning trend of illegal pharmaceutical imports and the potential for large-scale production exceeding individual usage limits. Between 2023 and 2025, Brazil imported 17.8 kg of semaglutide, enough to produce around 4 million Ozempic pens, while tirzepatide, which has not yet been approved in Brazil, accounted for 10 million doses.
Despite the potential benefits of these medications for individuals with type 2 diabetes, including improved glycemic control and reduced risk of cardiovascular complications, the growing trend of using these drugs for weight loss without medical oversight poses significant health risks.
The discussion around the prescription retention policy began last November but faced multiple delays. Initially postponed due to the need for further technical review, the topic resurfaced amid growing concerns from medical professionals and health organizations about the implications of unrestricted access to these drugs.
In response to the new regulations, the pharmaceutical industry has expressed mixed reactions. While some advocate for maintaining the current system without prescription retention, others recognize the need for stricter controls to ensure the safe use of these medications. The Interfarma association has called for a complete ban on the compounding of GLP-1 analogs in pharmacies, arguing that the current regulations do not adequately address the rising parallel market for these drugs.
As Brazil grapples with an obesity epidemic—current studies indicate that 56% of Brazilian adults are overweight, with 34% classified as obese—the need for effective regulation and responsible medical oversight has never been more critical. The new Anvisa policy aims to ensure that those who truly need these medications have access while mitigating the risks associated with their misuse.
In conclusion, the mandatory retention of medical prescriptions for weight-loss medications represents a pivotal step in addressing the growing concern over the misuse of these drugs in Brazil. As the new regulations take effect, they will be closely monitored to assess their impact on public health and the accessibility of these essential treatments.
