The injection potentiates weight loss, but patients must do their own work.
Tirzepatida can produce over 20% body weight loss when combined with lifestyle changes, but requires strict medical oversight and is not for cosmetic weight loss. The medication reduces appetite significantly but demands rigorous nutritional monitoring to prevent muscle loss, which can be as dangerous as obesity itself.
- Tirzepatida can produce over 20% body weight loss when combined with lifestyle changes
- Monthly treatment costs range from approximately R$730 to R$3,500 depending on dose and formulation
- Muscle loss during weight loss can be as dangerous as obesity itself, requiring strict nutritional oversight
- Rebound weight gain after stopping the drug without sustained lifestyle changes leaves patients metabolically worse off
A Brazilian university hosted a lecture on tirzepatida weight-loss injections, emphasizing their clinical benefits for obesity treatment while warning against misuse without medical supervision and highlighting the need for nutritional support.
On a Monday evening in Francisco Beltrão, a lecture hall at Universidade Paranaense filled with pharmacy, nutrition, and biomedical students gathered to hear a surgeon speak about weight-loss injections. Márcio Schenato, a local physician specializing in digestive and metabolic surgery, had come to discuss tirzepatida—a drug that has become central to obesity treatment and type 2 diabetes management. The event, organized by professors Patrícia Velasquez and Ediane Pissaia, drew enough interest to pack the auditorium.
Schenato opened by framing tirzepatida within the longer history of GLP-1 analog medications, then made his position clear: he considers this molecule transformative for clinical practice. The evidence supports his enthusiasm. Studies show the drug can produce weight loss exceeding 20 percent of body weight when patients also change their eating and exercise habits. But Schenato was careful to distinguish between clinical application and casual use. These injections, he emphasized, are not for people seeking to shed a few kilograms for appearance alone. They are medications for a chronic disease—obesity itself—which he argued should be treated by the public health system because it prevents cascading complications: cancer, heart disease, liver damage, and metabolic disorders that compound over time.
The drug works partly through appetite suppression. Patients on tirzepatida report feeling almost no hunger, which helps break the pattern of constant snacking and grazing throughout the day. Yet this mechanism creates a paradox that Schenato stressed repeatedly: the medication can mask the body's need for adequate nutrition. Without rigorous oversight from a nutritionist, patients risk losing muscle mass along with fat—a condition called sarcopenia that Schenato said kills as reliably as obesity does. He insisted on three non-negotiable elements: sufficient protein intake, supplementation when needed, and regular physical activity. The injection potentiates weight loss, he explained, but patients must do their own work. The drug is not a substitute for changed behavior; it is a tool that works only alongside it.
Beyond weight loss, tirzepatida produces secondary benefits that Schenato detailed: improved kidney function, lower blood pressure, reduced cholesterol and triglycerides, decreased cardiovascular risk, better sleep apnea, improved liver fat accumulation, restored insulin sensitivity, and in women with polycystic ovary syndrome, improved fertility. These cascading improvements explain some of the clinical excitement around the molecule.
But Schenato did not minimize the risks. Gastrointestinal discomfort occurs in some patients. Pancreatitis risk increases. Gallstones can form in susceptible individuals. Most concerning to him was what happens when patients stop taking the drug without sustaining their lifestyle changes. Weight returns—but the composition changes. Patients regain fat while having lost muscle, leaving them metabolically worse off than before treatment began. He also addressed a practical reality in his region: people buying tirzepatida across the border in Paraguay without medical supervision. Some of those products are legitimate; others are counterfeit. Without professional guidance, patients cannot know what they are actually injecting.
The cost matters too. Monthly expenses range from roughly 730 to 3,500 Brazilian reals depending on the specific medication and dose. Schenato argued that physicians must consider patients' financial reality when recommending treatment, acknowledging that access is not universal.
Schenato closed by speaking directly to the students in the room—the future pharmacists, biomedical scientists, and nutritionists who will manage these patients. They need to understand tirzepatida deeply, he said, because it is not going away. The drug represents a genuine therapeutic advance. But its full potential depends on something no injection can provide: a coordinated team of health professionals who know the molecule, monitor the patient, and hold the line between clinical benefit and harm.
Notable Quotes
For me, tirzepatide is the molecule of the century.— Márcio Schenato, digestive and metabolic surgeon
Sarcopenia kills as reliably as obesity does.— Márcio Schenato, on the dangers of muscle loss during weight loss treatment
The Hearth Conversation Another angle on the story
Why did Schenato spend so much time warning against misuse if the drug is so effective?
Because effectiveness and safety are not the same thing. A powerful tool in the wrong hands becomes dangerous. He was speaking to students who will eventually counsel patients, and he needed them to understand that tirzepatida is not a shortcut—it is a commitment.
The muscle loss issue seems to be what worried him most.
Yes. He said sarcopenia kills as reliably as obesity. That is not hyperbole in his view. You can lose weight and still end up sicker if you lose the wrong kind of mass. That is why he kept returning to nutrition and exercise—they are not optional add-ons, they are the actual treatment.
What about the people buying it in Paraguay without a doctor?
That is the reality he was addressing. In his region, people cross the border and buy these injections without prescription or follow-up. Some products are real, some are fake. He was essentially saying: if you do this, you do not know what you are putting in your body, and you have no one watching for complications.
Did he think the public health system should cover it?
He argued it should, because obesity is a chronic disease that causes other diseases. Treating it prevents cancer, heart problems, liver damage. From a public health perspective, it saves money downstream. But he also acknowledged the cost is high—up to 3,500 reals a month—so access is not simple.
The rebound weight gain after stopping—is that permanent?
Not necessarily permanent, but it is worse than the starting point if the patient has lost muscle. You regain fat without the muscle you had before. That is why he said the drug only works if the patient changes their life. Stop the injection and go back to old habits, and you are metabolically worse off than you started.
Why address the students specifically at the end?
Because they will be the ones patients actually talk to. The pharmacist fills the prescription. The nutritionist plans the meals. The biomedical scientist may run the tests. He was telling them: you need to know this molecule as well as the doctor does, because you are part of the team that keeps the patient safe.