Medically reviewed by Dr. Robert Rubin, MD. Last reviewed September 2026.
While the clinical evidence is clear in the head-to-head SURMOUNT-5 trial, published in 2024, that the weight loss with Tirzepatide is greater than with Semaglutide, that's not all that's relevant in your choice. Tirzepatide's clinical edge is most pronounced in patients with higher starting BMI or insulin resistance. Semaglutide may suit patients with specific cardiovascular history, insurance coverage constraints, or who have already had a positive response to a GLP-1. Neither answer is universal — this is exactly why a functional medicine evaluation matters before starting either medication.
Two GLP-1 medications dominate the conversation around medically assisted weight loss right now: Semaglutide vs. Tirzepatide. Semaglutide is sold under the brand name Wegovy for weight loss, while Tirzepatide is sold as Zepbound.
Patients ask about both constantly: What's the difference between Tirzepatide and Semaglutide? Which is better? How do they compare? Which one is right for me?
The honest answer is that they work through related but distinct mechanisms, produce different average weight loss results, and aren't equally “right” for every person. This post explains the key differences so you can have a more informed conversation with your physician.
GLP-1 medications like Semaglutide work by mimicking a natural hormone in your body called GLP-1 (glucagon-like peptide-1). When you eat, this hormone is released to tell your body it is full, but the natural version breaks down in just a few minutes. GLP-1 medications are designed to last much longer, targeting several key systems at once to manage blood sugar levels and weight. Our Semaglutide Weight Loss Program works through four primary actions achieved by this GLP-1 medication:
Tirzepatide adds GIP receptor agonism on top of GLP-1 action. What GIP does involves appetite suppression via a separate pathway, together with possible effects on fat metabolism. This is the structural reason Tirzepatide shows higher weight loss in trials.
It's important not to qualify Tirzepatide as simply “better” — the mechanism produces a quantitatively different outcome for most patients, but candidate fit still matters most.
In the SURMOUNT-5 trial, published in 2024, participants taking Tirzepatide lost a mean of 20.2% of their body weight compared to 13.7% for Semaglutide 2.4mg at 72 weeks. Additionally, registration data from the SURMOUNT-1 trial showed up to 22.5% body weight reduction with the 15mg Tirzepatide dose, while the STEP-1 trial demonstrated up to 15% average weight loss with Semaglutide. For more details, visit American College of Cardiology.
| Semaglutide | Tirzepatide | |
|---|---|---|
| Receptor targets | GLP-1 | GLP-1 + GIP |
| Average weight loss | ~15% of body weight | ~20% of body weight |
| Dosing | Weekly injection | Weekly injection |
| FDA approval (obesity) | 2021 (Wegovy) | 2023 (Zepbound) |
| Compounded available | Yes | Yes |
Both drugs share a similar GI side effect profile — nausea, vomiting, constipation — most pronounced during dose escalation. Tirzepatide may carry slightly higher rates at peak doses, but serious adverse events are rare with either. Dr. Rubin's practice uses compounded formulations and a gradual titration protocol to minimize tolerability problems. He also conducts a comprehensive medical weight loss evaluation to develop an individualized plan, with the right medication at the right dose and formulation to ensure tolerability.
Tirzepatide's clinical edge is most pronounced in patients with higher starting BMI or insulin resistance. Semaglutide may suit patients with specific cardiovascular history, insurance coverage constraints, or who have already had a positive response to a GLP-1. Neither answer is universal — this is exactly why a functional medicine evaluation matters before starting either medication.
Dr. Rubin's program begins with a comprehensive functional evaluation before recommending any medication. That evaluation looks at metabolic markers, hormone levels, body composition, and lifestyle factors that influence how well each drug works for a given patient. The goal is not to prescribe the medication with the best population-level data but to match the right tool to the individual's physiology.
At Improving Your Health, located in Naples and Tampa, we take a Functional Medicine approach to medical weight loss that is designed to correct underlying cause(s) of chronic conditions or symptoms. Discover the difference medications like Tirzepatide and Semaglutide can make in your weight loss journey, as well as your overall health and wellbeing.
For patients in Tampa, learn more about Semaglutide and Tirzepatide weight loss. If you are in Naples, explore our Tirzepatide and Semaglutide weight loss programs.
Dr. Robert D. Rubin specializes in functional medicine, bioidentical hormones, weight loss therapy, and sexual health treatments. Dr. Rubin is a widely respected functional medicine practitioner in Florida with offices in Naples and Tampa, as well as a convenient telemedicine treatment program. He has extensive experience treating patients who are struggling with longevity and health concerns.
As an Advanced Fellow in the American Academy of Anti-Aging Medicine, who is also AMA Board Certified in Internal Medicine and Geriatrics Medicine, Dr. Rubin is a dedicated medical professional with an exceptional track record. He spent the first 25 years of his medical career working in internal and geriatric medicine, successfully becoming one of Palm Beach County's top-rated physicians. For four years, Castle Connolly Medical, Ltd. recognized him as one of the “Top Doctors” in South Florida.
After further specialized training, he shifted his practice to a functional medicine approach to better serve the needs of his patients. Over the last 15 years, Dr. Rubin has honed his focus, creating a practice rooted in evidence-based healthcare that addresses the root causes of your symptoms.
Combining this with his expertise in Internal Medicine and Geriatrics, he provides a comprehensive approach to your health. Dr. Rubin always takes an individualized approach to treatment, recognizing that each patient has a different medical history, symptoms, and underlying issues. Listening attentively to your concerns, Dr. Rubin personalizes a treatment protocol to meet your needs, guiding you confidently on your lifelong health journey.
To revolutionize your approach to weight loss, book online or call either of our offices today for in-person or telemedicine options.
