By Luciana Magalhaes
SAO PAULO, Aug 31 (Reuters) - When Brazilian customs agents opened jars of dulce de leche aboard a tourist bus arriving from Paraguay in April, they discovered hundreds of vials of tirzepatide, the active ingredient in the popular weight-loss drug Mounjaro, mixed inside the sweet spread.
The routine inspection turned into one of Brazil's largest seizures of weight-loss medications, with the total shipment exceeding 2,500 vials, according to the Federal Revenue Service. But it was
hardly an anomaly.
Along that border, agents are finding slimming drugs, part of a class of pharmaceuticals called GLP-1 receptor agonists, in unexpected places.
Drugs hidden in motorcycle exhaust pipes and false shoe soles underscore the dangers of a boom that has made Brazil one of the world's hottest markets for weight-loss medications, including Eli Lilly's Mounjaro and Novo Nordisk's Wegovy, which has the active ingredient semaglutide.
Health officials and experts worry the country may be one of the most exposed to the weight-loss boom's unintended consequences, as a beauty-conscious culture, limited purchasing power, and weak law enforcement drive consumers toward smuggled and unapproved injections.
Between 2018 and mid-August 2026, Brazilian authorities recorded 83 deaths, which are under investigation, and over 3,600 complications linked to weight-loss drugs. They were notified of more than 60% of the complications in 2025 and 2026.
Untracked versions of the drugs have likely played a significant role, they said. Some 51% of the country's estimated $7 billion weight-loss drug sales this year are expected to come from pharmacies that custom-mix medications and products smuggled from Paraguay, according to investment bank Itau BBA. Reuters could not independently establish the role unauthorized GLP-1 versions have played in those deaths and complications.
While experts told Reuters they fear a public health crisis, three Brazilians said the risks are worth it.
"There is always some fear," said Taiane Torres da Silva, a pet groomer in Rio de Janeiro who buys a Paraguayan drug called T.G., which Brazilian health authorities have not vetted. "But we do it anyway because we want to lose weight."
Paraguay's health regulator, Dinavisa, which has approved T.G., said in a statement that neither it nor the Paraguayan government is responsible for transporting medicines, although it acknowledged that some citizens do so "irresponsibly."
T.G. is manufactured in Paraguay by Laboratorios Indufar Cisa, which did not respond to requests for comment.
Pharmacies in Paraguay legally sell T.G., including to Brazilians.
According to Brazil's health regulator Anvisa, only smuggled products bypass official evaluation. The custom-mixed "compounded" medications must meet technical standards and pass local inspections.
However, Andreia Kohout, pharmaceutical director of the Brazilian Anti-Counterfeiting Association, said consumers often mistakenly view compounded drugs as identical to brand names. The compounded medication market, which influencers frequently promote, also features unreliable suppliers, she said.
Asked to comment on the smuggling, prices, and competition from untracked drugs, Eli Lilly said it supports Brazilian authorities in combating the illegal market to protect patient safety. Regarding prices, it said it continues to seek ways to increase affordability within legal, regulated and safe parameters.
"In Brazil, the rising popularity of GLP-1 drugs has boosted the market for compounded, counterfeit, or illegally imported products, often sold without medical supervision or outside regulated channels," said Novo Nordisk, adding that it focuses on providing overall value through evidence-based treatments, education, patient support, program discounts, and a partnership with a local manufacturer.
The proliferation of weight-loss treatments has cemented Brazil's standing as a global beauty hub, along with Turkey and South Korea. For decades, residents and tourists have flocked to its cosmetic and plastic surgery centers for treatments, which many foreigners can access at attractive prices.
Brazil's GLP-1 usage rate, at 5.5% of the population, exceeds the global average of 3.7%, according to market research firm Euromonitor International, meaning millions of people have tried the treatments.
Nationwide seizures of illegal GLP-1 weight-loss drugs are soaring, from 609 units in 2024 to 60,787 in 2025, according to the Anti-Counterfeiting Association. Seizures have continued to rise sharply this year.
HEALTH RISKS MOUNT
What alarms some experts and officials is not just the volume of intercepted drugs, but the manner in which they are manufactured and transported. Two doctors, a pharmacist and a Brazilian official told Reuters that poor storage and heat exposure can ruin injections.
Labeling for Mounjaro and Wegovy also notes the risk of acute pancreatitis, affecting 0.1% to 1% of patients. One of the doctors said prolonged fasting while taking the drugs can cause hypoglycemia, though rarely when the medications are used correctly. Additionally, health regulator Anvisa has warned of aspiration and pneumonia risks during anesthesia because the drugs slow digestion.
Earlier this year, the regulator also noted a rising number of reports of acute pancreatitis, which can progress to cell and tissue death, and even fatal forms, linked to the improper use of GLP-1s. It said the drugs must be used as prescribed, under medical supervision.
'IT HAS BECOME DRUG TRAFFICKING'
Dr. Leonardo Sebba, who treats obesity in Goias, a state in Brazil's Center-West region, said he has seen some patients become severely constipated after taking weight-loss drugs often sourced through unofficial channels. Constipation can be a side effect of the brand-name drugs too.
At least one of Sebba's patients required surgery for intestinal complications.
"Unfortunately, the medication is everywhere, in pharmacies, but also at street markets, hair salons, the gym, and with neighbors," Sebba said. "It has really become, and it is a strong word, drug trafficking."
The illegal injections come mostly from Paraguay, where more lax patent laws allow companies to manufacture products that are otherwise only available as more expensive, brand-name drugs.
Paraguay's health regulator said the use of smuggled drugs in Brazil falls under the purview of Brazilian authorities. Brazil's revenue service said its officers act broadly to stop the entry of illegal goods, but has no operation targeting weight-loss drugs.
Illicit weight-loss drugs can cost a fraction of the drugstore price.
Silva, the pet groomer from Rio, earns Brazil's minimum wage, $300 a month, and buys the T.G. Paraguayan weight-loss drug for about $75 every six weeks.
In Brazil, a four-week supply of Mounjaro costs about $290 for the lowest dose, 2.5 mg. A high-dose, 2.4-mg Wegovy box sells for close to $340 online through a patient support program. Their doses are not comparable because they have different active ingredients.
AUTHORITIES APPROVE CHEAPER ALTERNATIVES
Brazilian authorities hope the availability of cheaper, authorized weight-loss drugs may help drive customers away from illegally obtained injections.
In May, Brazil's regulatory agency approved Ozivy, the country's first domestic alternative to Novo Nordisk's Ozempic, which can sell for less than $100 for a four-week supply. Since then, Anvisa has approved other brands.
"Controlling demand is difficult," Anvisa Director-President Leandro Safatle told reporters this month. "But if that demand is already being met by a regulated, safer product priced similarly to unauthorized imports, people will naturally choose the regulated option."
Pamela Erculano Silva, a nurse in Rio de Janeiro who recently lost 17 kg (37 pounds), also uses the T.G. brand smuggled from Paraguay because it is affordable and easy to buy from an acquaintance.
"It completely transformed my quality of life and self-esteem," she said.
DEATHS UNDER INVESTIGATION
Officials are investigating over 80 deaths linked to weight-loss drugs in Brazil. Flavio Fabres, who heads the medical examiner's office in João Pessoa, in the northeastern state of Paraiba, reviewed one of them.
Last November, he performed the autopsy of 31-year-old Jessica Ataide, who died suddenly while using the medication without consulting a health professional, Fabres said.
Shortly after a dose, her blood sugar plummeted, triggering severe hypoglycemia. She lost consciousness and choked.
"The stomach contents entered her airway, which ultimately led to her death by asphyxiation," Fabres said.
Ataide's family declined to comment on her death.
Reuters could not establish what type of weight-loss drug she had been using.
Still, some Brazilians say they will not stop taking them.
Vitoria Braga, a 31-year-old Rio resident who is taking a smuggled weight-loss injection along with her boyfriend and three relatives, said she never consulted a doctor, even when a recent dose increase left her bedridden for four days with fever, nausea, and flu-like symptoms.
"I do not even know who the supplier is," she said. "The doctor would have said I was crazy and told me to stop."
(Reporting by Luciana Magalhaes, with additional reporting from Ricardo Brito, in Brasilia and Daniela Desantis, in Asuncion, editing by Manuela Andreoni and Rod Nickel)
