The phone calls started in 2022 and never really slowed down. Patients asking Dr. Nikolas Antoniou whether they qualified for Ozempic. Whether Wegovy was different. Whether Zepbound was better. Whether the compounded version a friend was buying online was safe.
Dr. Antoniou, who has practiced family medicine in the Chicago area for three decades, has watched a category of medication move from diabetes clinics to dinner table conversations in less than three years. GLP-1 receptor agonists, and their newer dual-action cousins, have changed what is possible in the treatment of obesity and type 2 diabetes. They have also generated a level of confusion, hype, and online misinformation that he says he has rarely seen rivaled in his career.
“These are real medications doing real things,” Dr. Antoniou said. “They are also being talked about as if they are a shortcut, and they are not. The patients who do well on them are the ones who understand what the medication is actually for.”
What GLP-1 medications actually do
GLP-1 stands for glucagon-like peptide-1, a hormone the body produces naturally after eating. Medications in this class, including semaglutide, sold as Ozempic for diabetes and Wegovy for weight management, mimic that hormone. They slow gastric emptying, signal fullness to the brain, and improve insulin sensitivity. Tirzepatide, sold as Mounjaro and Zepbound, adds a second mechanism by also targeting the GIP receptor.
In clinical trials, the results are striking. Patients on semaglutide have averaged about 15 percent body weight loss over roughly 16 months. Tirzepatide has produced averages closer to 20 percent. For comparison, lifestyle programs alone typically produce 5 to 7 percent.
Dr. Antoniou is direct about what those numbers represent. For patients with obesity, type 2 diabetes, or both, this is the most effective pharmacological intervention the field has ever had. For some of his patients, it has been transformative. Blood pressure improves. A1C numbers are dropping into the normal range. Sleep apnea easing. Joint pain is improving as weight comes off.
What they are not
They are not a cure. They are not a replacement for behavior change. They are not, in Dr. Antoniou’s view, the right tool for someone trying to lose ten vanity pounds before a wedding.
The medications work as long as patients are taking them. When patients stop, studies show that most regain a substantial portion of the weight they lost, often within a year. That is not a failure of the patient. It is how the underlying biology of obesity works. Hunger hormones return. Metabolic adaptations persist. The medication was managing a chronic condition, and stopping it produces the same kind of rebound a patient would expect from stopping blood pressure medicine.
“Patients sometimes hear that and feel betrayed,” Dr. Antoniou said. “They thought they were taking a course of treatment, like an antibiotic. They were taking a medication for a chronic condition. Those are different things, and the conversation about that needs to happen before the first prescription, not after.”
The side effects patients underestimate
Nausea is the most common complaint, especially during dose escalation. Most patients tolerate it. Some do not. Constipation, reflux, and fatigue are also routine. Dr. Antoniou has seen patients abandon the medication in the first month because no one prepared them for what the early weeks would feel like.
More serious risks exist and need monitoring. Pancreatitis is rare but real. Gallbladder disease can flare. Patients with a personal or family history of medullary thyroid carcinoma should not take these medications. Patients with significant gastroparesis are not good candidates. Muscle mass loss accompanies fat loss, which is one reason Dr. Antoniou recommends high-quality protein intake and resistance training during treatment.
None of this is a reason to avoid the medication. It is a reason, he says, to get it from a doctor who knows the patient.
The role of family medicine
Obesity is a chronic disease. The 2013 reclassification by the American Medical Association acknowledged what family physicians had been seeing for decades. It is not a willpower problem. It is a metabolic, genetic, hormonal, and environmental condition that responds to medical treatment the way other chronic diseases do.
Dr. Antoniou believes family medicine is the right setting for most of these conversations. A primary care doctor sees the patient’s full picture. Blood pressure, cholesterol, blood sugar, mental health, family history, medications, sleep, mobility. The decision about whether to start a GLP-1, which one, at what dose, and for how long, depends on all of it.
He also believes the conversation has to be honest. The medication is not magic. It is a tool that works best when paired with realistic expectations, nutritional changes, resistance training, and a long-term plan. Patients who treat it as a one-year fix tend to be disappointed. Patients who treat it as part of how they manage a chronic condition tend to do well.
Where the conversation should start
For patients curious about whether a GLP-1 might be right for them, Dr. Antoniou suggests starting with a primary care visit. Bring weight history, family history of diabetes or heart disease, current medications, and an honest accounting of what previous attempts at weight management have looked like. Expect a real discussion of risks, costs, and alternatives, including whether lifestyle changes alone might be enough.
And expect, he says, a doctor who takes the question seriously. The era of telling patients with obesity to simply eat less and move more is, in his view, finally ending. The science has moved on. Primary care needs to move with it.
“This is one of the most important shifts in chronic disease management in a generation,” Dr. Antoniou said. “My job is to help patients make sense of it without falling for the hype, and without missing the genuine progress.”