The National Health Surveillance Agency (Anvisa) in Brazil has sounded an alarm about the risks associated with the misuse of weight loss pens, noting that one of the potential adverse effects is acute pancreatitis, a condition that can be fatal. The agency pointed out that although this risk has always been mentioned in the product leaflets, there has been a notable increase in global cases of pancreatitis among users of these weight loss injections, prompting a stronger notification to the public.

From 2020 to December 7, 2025, there have been 145 suspected adverse events reported in Brazil linked to the use of these pens. Authorities are currently investigating whether six fatalities could be connected to injections from these products. Anvisa emphasized that inappropriate use, particularly for weight loss without a medical necessity, significantly heightens health risks, thus raising concerns about the trend of using these medications without proper guidance.

Weight loss pens refer to a popular class of injectable medications, including dulaglutide, liraglutide, semaglutide, and tirzepatide, which are intended for specific clinical uses. The agency's warning underscores the importance of adhering to approved uses and the dangers of self-prescribing these treatments without medical oversight, as adverse outcomes such as pancreatitis could become more prevalent if misuse continues unchecked.