The Friendship Bridge, which connects Brazil and Paraguay near the iconic Iguazu Falls, has long been used as a route for smugglers transporting cheap illegal goods such as cigarettes and electronics. But Brazilian authorities say in recent years smugglers have discovered a much more lucrative product: weight loss drugs.
As demand for GLP-1-based medicines soars in Brazil, seizures of unlicensed weight-loss drugs are rapidly increasing along the Brazil-Paraguay border. More than 76,000 pens, vials and other products containing drugs such as semaglutide and tirzepatide were seized at borders in the first half of 2026, nearly triple the number seized in all of last year, according to data from Brazil’s Federal Revenue Agency.
The surge has made weight loss drugs one of the most valuable categories of contraband seized in the region, as smugglers take advantage of a surge in demand in Brazil and sharply lower prices across the border. Experts say the trade is increasingly attracting organized crime groups because the products are lucrative and relatively easy to transport.
However, medical professionals have warned of the negative effects of purchasing these medicines through informal sellers. Consumers may not have a reliable way to know exactly what they are injecting themselves with.
But federal tax inspector Flavio Bernardino de Carvalho said the drug is now the second-most valuable item seized by federal revenue authorities in the region, which includes the southern states of Paraná and Santa Catarina, after cell phones.
“They come in public buses, cars, trucks, tourists. They come in all kinds of ways,” Carvalho told CNN Brasil. “There’s organized crime and there’s individuals. It’s very dispersed.”
Brazilian authorities estimate that more than 100,000 people and 45,000 vehicles pass through the Friendship Bridge each day at peak times, posing a major challenge for customs officials trying to identify illegal cargo. As such, the bridge has long been one of the busiest smuggling corridors in South America.
Tracing the origin of smuggled weight loss jabs is often impossible. Paraguayan authorities say some of the drug is sold legally in Paraguay, then stolen from local pharmacies and smuggled across the border, while police have also uncovered an undercover operation manufacturing counterfeit versions of the drug in the country.
Carlos Duret, head of the Tripartite Command, a police coalition between authorities from Argentina, Brazil and Paraguay, which share borders in the region, told the Organized Crime and Corruption Reporting Project that Chinese imports of the drug were also discovered.
Mounjaro, the only tirzepatide treatment approved in Brazil by American pharmaceutical company Eli Lilly & Company, can cost more than 1,400 reais (about $280). In Paraguay, an ampoule of locally produced tirzepatide sells for about 340 reais (about $68), according to Brazil’s Federal Revenue Agency.
Public security expert José Ricardo Bandeira told CNN Brazil that these economic conditions are changing the motivations of criminal groups that have historically profited from tobacco smuggling.
“Organized crime is migrating. There’s a point to that,” Bandeira said. “Tobacco smuggling requires a huge amount of logistics: trucks to transport the cigarettes and a series of measures to bring the contraband into Brazil.”
The small size of weight loss drugs makes logistics easier and much more cost-effective. According to Federal Revenue Service data, a pack of cigarettes costs about 850 times less than a bottle of tirzepatide, but it is bulkier to transport.
“Pens are more attractive because of their smaller size and higher value,” says Bandeira. “A few boxes of pens can make you the same profit as smuggling a truckload of cigarettes.”
Officials say smugglers are also using existing routes and infrastructure.
“Organized crime is reaching,” Bandeira said. “They share routes, they share storage centers. They use the same routes that they use to smuggle arms, drugs and ammunition.”
Hidden in shoes, shampoo bottles, and cars
Smugglers have resorted to creative methods to hide their products. Brazilian customs officials have found weight-loss drugs shoved under the soles of boots, stuffed inside shampoo bottles, hidden in massage gel containers and hidden in secret compartments of cars.
Other cargo bypasses the bridge entirely, and boats are used to transport cargo across the Paraná River, which forms part of the border between Brazil and Paraguay.
These methods raise issues beyond the illegality of the transaction. Injectable GLP-1 drugs require specific storage conditions.
Dr. Alexandre Hall, professor of endocrinology and metabolism at the Federal University of Santa Catarina and director of the Brazilian Obesity and Metabolic Syndrome Research Association, has long advocated against the illegal use of drugs.
“Anytime you look for medication outside of a pharmacy, you’re taking a risk,” Hall says.
He explained that legal medicines pass through a carefully controlled supply chain before reaching patients. Drugs such as semaglutide and tirzepatide are peptide molecules and require controlled conditions during transportation and storage. These conditions are unlikely to be met if illegal products are carried across borders hidden in vehicles, shoes or on people’s bodies, he said.
Hall said peptide drugs can lose stability when exposed to temperatures above 30 degrees Celsius (86 degrees Fahrenheit) or below 0 degrees Celsius (32 degrees Fahrenheit).
He said a possible consequence of improper storage is reduced efficacy, which could ultimately result in consumers paying less for drugs that don’t work as intended.
But the consequences could potentially be even more serious.
Hall said the bigger concern revolves around products whose origin or contents cannot be verified. “I don’t know where it came from. It’s not original,” he said. “They are copies manufactured somewhere unknown to us.”
The production of peptide drugs is technically complex. Hall said if the manufacturing process is not properly controlled, impurities can remain in the final product.
Known side effects of approved semaglutide and tirzepatide include nausea, constipation and diarrhea, he said. However, if the source of the drug is unknown, symptoms should be taken seriously if they persist or are unexpected.
Dr. Hall told CNN that he has seen patients who reported unusual side effects after taking vials of smuggled weight loss drugs.
One of his patients ended up in intensive care after using a product sold as tirzepatide from Paraguay. The woman, who was of normal weight and purchased the drug without a prescription or medical indication, developed lactic acidosis, a potentially serious buildup of acid in the blood.
In another case, Hall prescribed the approved version of tirzepatide to a patient, but after the first month, the patient switched to a product his father had purchased in Paraguay. Shortly thereafter, he developed nausea, vomiting, and diarrhea and was treated by a doctor. Despite his symptoms, he continued to use the Paraguayan product and further increased his dose, which ultimately led to him being admitted to the emergency room.
“Persistent nausea, abdominal pain, headaches and skin reactions are some of the symptoms I’ve seen so far,” he said, adding that side effects can be difficult to predict for drugs that are not carefully regulated and manufactured. “Immune system reactions, effects not seen when the original drug was studied, more severe side effects…these can potentially occur.”
Online orders related to GLP-1 medicines increased by 149.3% in Brazil in the first half of 2026, according to a study by Serasa Experian, a Brazilian private data and credit services company that analyzed GLP-1 orders through anti-fraud technology. Requests rose to more than 1.36 million between January and June, up from 547,249 in the previous six months, and purchases amounted to more than 2.3 billion reais (approximately $460 million).
As demand for weight loss drugs increases, Brazilian authorities are now stepping up cooperation with Paraguay to combat the growing illicit market.
Last Thursday, Brazil’s health regulator Anvisa signed an agreement with Paraguay’s National Health Surveillance Directorate (Dinavisa) to strengthen surveillance along the border between the two countries.
But the illicit market may already have outgrown the current generation of weight loss drugs.
Hall said one of his patients reported using a product sold as letaltortide, an experimental weight loss drug being developed by Eli Lilly and Co.
Retatortide has not been approved by the U.S. Food and Drug Administration or any other regulatory agency worldwide and is only legally available to participants in clinical trials sponsored by Lilly. The company reported positive results in several Phase 3 trials this year and said it plans to submit the drug to the FDA for approval in the first quarter of 2027.
However, a product sold as Letaltortide is already on sale in Paraguay. Hall said he has seen such products sold in the country and has encountered patients who have already used the products in Brazil.
Advertisements for weight loss drugs are widespread in Paraguay’s second city, Ciudad del Este, Brazilian officials say. Semaglutide and tirzepatide are also available for purchase without a required prescription through Brazil’s regulatory system.
Carvalho, the federal tax inspector, said authorities are increasingly confronting not only physical smuggling routes, but also online sales and social media, where sellers can advertise their products and users can exchange information on how to move goods across borders.
For Brazil’s health officials and doctors, that may be one of the most troubling aspects of the boom. The illegal market moves almost as fast as the pharmaceutical market.
“Access is very easy,” Hall said. “Nowadays, you can buy it online. You can buy it anywhere. But people need to be careful about what they put in their bodies.”
