Semaglutide vs. Tirzepatide: Complete Comparison
Two drugs dominate the GLP-1 conversation right now: semaglutide and tirzepatide. You know them by their brand names — Ozempic, Wegovy, Mounjaro, Zepbound. They've gone from niche diabetes medications to cultural phenomena in under three years.
Two drugs dominate the GLP-1 conversation right now: semaglutide and tirzepatide. You know them by their brand names — Ozempic, Wegovy, Mounjaro, Zepbound. They've gone from niche diabetes medications to cultural phenomena in under three years.
But if you're trying to figure out which one might work better for you — or simply trying to understand how they differ — the picture gets confusing fast. Marketing claims blur with clinical data. Social media anecdotes drown out trial results. And the drugs themselves, while related, work through meaningfully different mechanisms.
This guide cuts through all of it. We break down the clinical trial data, compare the side effect profiles, explain the cost picture, and help you understand what the science actually says about each drug — no hype, no oversimplification.
Table of Contents
- Quick Comparison Table
- How They Work: One Hormone vs. Two
- Brand Names and FDA Approvals
- Dosing Schedules
- Weight Loss: What the Trials Show
- The Head-to-Head Showdown: SURMOUNT-5
- Blood Sugar Control: A1c Reduction Data
- Cardiovascular Outcomes
- Side Effects Comparison
- Body Composition: The Muscle Loss Question
- Cost and Insurance Coverage
- Which One Is Right for You?
- The Bottom Line
- References
Quick Comparison Table
| Feature | Semaglutide | Tirzepatide |
|---|---|---|
| Mechanism | GLP-1 receptor agonist | Dual GIP/GLP-1 receptor agonist |
| Brand Names (Diabetes) | Ozempic, Rybelsus | Mounjaro |
| Brand Names (Weight Loss) | Wegovy | Zepbound |
| FDA Approval (Diabetes) | 2017 (Ozempic) | 2022 (Mounjaro) |
| FDA Approval (Obesity) | 2021 (Wegovy) | 2023 (Zepbound) |
| Max Dose | 2.4 mg/week (Wegovy) | 15 mg/week |
| Administration | Weekly injection or daily pill | Weekly injection |
| Avg. Weight Loss (Trials) | 13.7–16.9% | 20.2–22.5% |
| Avg. A1c Reduction | 1.0–1.9% | 2.0–2.3% |
| CV Outcomes Data | Proven 20% MACE reduction (SELECT) | Non-inferior to dulaglutide (SURPASS-CVOT) |
| Common Side Effects | Nausea, vomiting, diarrhea, constipation | Nausea, diarrhea, vomiting, constipation |
| List Price (Monthly) | ~$1,000–$1,600 | ~$1,000–$1,100 |
| Discount Programs | $349/month (self-pay) | $299–$449/month (self-pay) |
How They Work: One Hormone vs. Two
Understanding the mechanism behind each drug explains why their clinical results differ.
Semaglutide is a GLP-1 receptor agonist. It mimics a single gut hormone — glucagon-like peptide-1 (GLP-1) — that your body naturally releases after eating. When semaglutide binds to GLP-1 receptors in the brain, pancreas, and gut, it triggers a cascade of effects: increased insulin secretion, reduced glucagon output, slower gastric emptying, and — perhaps most relevant for weight loss — reduced appetite and increased satiety.
Tirzepatide goes a step further. It's a dual GIP/GLP-1 receptor agonist, meaning it mimics two gut hormones simultaneously: GLP-1 and glucose-dependent insulinotropic polypeptide (GIP). GIP is less well-known than GLP-1, but it plays a significant role in insulin secretion, fat metabolism, and energy balance. By activating both receptor systems at once, tirzepatide produces effects that neither hormone achieves alone.
Think of it this way: semaglutide presses one accelerator pedal. Tirzepatide presses two. The result, as you'll see in the trial data, is generally more weight loss and better blood sugar control — though the story is more nuanced than that.
The dual mechanism may also explain tirzepatide's effects on fat tissue specifically. Early research suggests GIP receptor activation influences adipocyte function — how fat cells store and release energy — in ways that GLP-1 alone does not. GIP signaling appears to affect lipid storage, triglyceride metabolism, and possibly even how the body distributes fat between visceral and subcutaneous compartments. This is an active area of investigation, and the exact contribution of each pathway is still being mapped out.
It's worth noting that both drugs are modified versions of their natural hormone counterparts. The modifications (fatty acid side chains that bind to albumin) extend their half-life from minutes to roughly a week — which is why a single weekly injection sustains therapeutic levels for seven full days.
Brand Names and FDA Approvals
Both semaglutide and tirzepatide are sold under different brand names depending on the indication. This causes constant confusion, so here's the breakdown:
Semaglutide (manufactured by Novo Nordisk):
- Ozempic — FDA-approved for type 2 diabetes (2017). Injection, max dose 2.0 mg/week.
- Rybelsus — Oral tablet form for type 2 diabetes (2019). Up to 14 mg daily.
- Wegovy — FDA-approved for chronic weight management (2021). Injection, max dose 2.4 mg/week. Also available as a daily pill (approved 2025), max 25 mg/day.
Wegovy also carries an FDA indication for reducing cardiovascular events in adults with obesity and established heart disease, based on the SELECT trial results. It's approved for adolescents aged 12 and older with obesity.
Tirzepatide (manufactured by Eli Lilly):
- Mounjaro — FDA-approved for type 2 diabetes (2022). Max dose 15 mg/week.
- Zepbound — FDA-approved for chronic weight management (2023). Max dose 15 mg/week.
Zepbound also carries an FDA indication for moderate-to-severe obstructive sleep apnea in adults with obesity, based on the SURMOUNT-OSA trial. In early 2025, Mounjaro received approval for children aged 10 and older with type 2 diabetes.
For a deeper look at how the diabetes and weight loss versions of semaglutide compare, see our guide on Ozempic vs. Wegovy. For the Novo Nordisk vs. Eli Lilly brand comparison, see Ozempic vs. Zepbound.
Dosing Schedules
Both drugs use a gradual dose-escalation approach. You start low and increase over several months to give your GI system time to adapt. Rushing the escalation is the single biggest predictor of intolerable nausea.
Semaglutide (Wegovy) Injection Escalation
| Weeks | Dose |
|---|---|
| 1–4 | 0.25 mg/week |
| 5–8 | 0.5 mg/week |
| 9–12 | 1.0 mg/week |
| 13–16 | 1.7 mg/week |
| 17+ | 2.4 mg/week (maintenance) |
Time to maximum dose: approximately 16 weeks. If 2.4 mg isn't tolerated, 1.7 mg is an acceptable maintenance dose.
Tirzepatide (Zepbound) Injection Escalation
| Weeks | Dose |
|---|---|
| 1–4 | 2.5 mg/week |
| 5–8 | 5.0 mg/week |
| 9–12 | 7.5 mg/week |
| 13–16 | 10 mg/week |
| 17–20 | 12.5 mg/week |
| 21+ | 15 mg/week (maintenance) |
Time to maximum dose: approximately 20 weeks. Maintenance can be set at 5, 10, or 15 mg depending on response and tolerability.
Both are administered as once-weekly subcutaneous injections using pre-filled pens. Semaglutide also comes in a daily oral pill form (Rybelsus for diabetes; Wegovy pill for weight loss).
For tips on managing side effects during dose escalation, see our guide on how to manage GLP-1 side effects.
Weight Loss: What the Trials Show
Before the drugs faced each other directly, separate clinical trial programs established their individual weight loss profiles.
Semaglutide: The STEP Trials
The STEP trial program tested semaglutide 2.4 mg for weight loss across multiple populations:
- STEP 1 (adults with obesity, no diabetes): 16.9% mean body weight reduction at 68 weeks vs. 2.4% with placebo. Participants lost an average of 15.3 kg (33.7 lbs) (Wilding et al., NEJM, 2021).
- STEP 2 (adults with obesity and type 2 diabetes): 9.6% weight loss at 68 weeks vs. 3.4% with placebo.
- STEP 3 (with intensive behavioral therapy): 16.0% weight loss at 68 weeks.
- STEP 5 (extended 104-week data): Weight loss was maintained through two years of treatment.
Tirzepatide: The SURMOUNT Trials
The SURMOUNT trial program tested tirzepatide for weight loss:
- SURMOUNT-1 (adults with obesity, no diabetes): 22.5% mean weight reduction at the highest dose (15 mg) over 72 weeks vs. 2.4% with placebo. That translates to an average of 23.6 kg (52 lbs) lost (Jastreboff et al., NEJM, 2022).
- SURMOUNT-2 (adults with obesity and type 2 diabetes): 15.7% weight loss at the highest dose over 72 weeks.
- SURMOUNT-3 (with intensive lifestyle intervention lead-in): 26.6% total weight loss from pre-randomization baseline.
- SURMOUNT-4 (withdrawal study): Participants who switched from tirzepatide to placebo regained roughly half the weight they'd lost over 36 weeks.
Even in their separate programs, the pattern was clear: tirzepatide consistently produced larger weight reductions across every population tested. The SURMOUNT-4 withdrawal data also highlighted something important: when patients stopped tirzepatide after 36 weeks and switched to placebo, they regained roughly half the weight they'd lost over the following 36 weeks. STEP 4 showed a similar pattern for semaglutide. These withdrawal studies established that both drugs require ongoing treatment to maintain results — a finding that reframes them as chronic disease management tools rather than short-term interventions.
But separate trial programs use different patient populations, eligibility criteria, and protocols, making indirect comparison imprecise at best. That's why the head-to-head trial mattered so much.
The Head-to-Head Showdown: SURMOUNT-5
The trial the field had been waiting for landed in May 2025. Published in the New England Journal of Medicine, SURMOUNT-5 was the first randomized controlled trial to directly pit tirzepatide against semaglutide for obesity treatment.
Study Design
Researchers enrolled 751 adults with obesity (BMI 30+) or overweight with at least one weight-related comorbidity, but without type 2 diabetes, across 32 sites in the United States and Puerto Rico. Participants were randomly assigned 1:1 to receive:
- Tirzepatide: maximum tolerated dose of 10 or 15 mg weekly
- Semaglutide: maximum tolerated dose of 1.7 or 2.4 mg weekly
Treatment lasted 72 weeks. The trial was open-label — both patients and doctors knew which drug was being used — a limitation worth noting, though the primary endpoint (weight change) is an objective measurement less susceptible to observer bias.
The Results
| Outcome | Tirzepatide | Semaglutide |
|---|---|---|
| Mean % body weight loss | 20.2% | 13.7% |
| Mean absolute weight loss | 22.8 kg (50.3 lbs) | 15.0 kg (33.1 lbs) |
| Waist circumference reduction | 18.4 cm | 13.0 cm |
| Achieved ≥10% weight loss | 82% | 67% |
| Achieved ≥15% weight loss | 64% | 43% |
| Achieved ≥20% weight loss | 48% | 27% |
| Achieved ≥25% weight loss | 32% | 16% |
Tirzepatide was statistically superior on every measure (P<0.001 for the primary endpoint). In relative terms, tirzepatide produced 47% more weight loss than semaglutide.
An important detail: 35% of participants were men, a higher proportion than most obesity trials. Weight loss was about 6% lower in men than women in both treatment groups — a finding the authors believe partially explains why the overall weight loss numbers were slightly more modest than in SURMOUNT-1.
What This Means
SURMOUNT-5 confirmed what the separate trial programs had suggested: tirzepatide's dual mechanism produces meaningfully greater weight loss. A 6.5 percentage point difference is not trivial. For a 250-pound person, that's the difference between losing roughly 34 pounds (semaglutide) and 50 pounds (tirzepatide).
A post-hoc analysis published in the European Heart Journal Open estimated that the greater weight and metabolic improvements with tirzepatide could translate to approximately 2 million fewer cardiovascular events over 10 years if applied to the eligible U.S. population, compared to 1.15 million with semaglutide (Sattar et al., 2025).
Blood Sugar Control: A1c Reduction Data
For people with type 2 diabetes, the comparison on glycemic control is just as relevant as weight loss.
SURPASS-2: Head-to-Head in Type 2 Diabetes
The SURPASS-2 trial, published in the NEJM in August 2021, randomized 1,879 adults with type 2 diabetes on metformin to receive tirzepatide (5, 10, or 15 mg) or semaglutide (1 mg) for 40 weeks (Frias et al., NEJM, 2021):
| Metric | Tirzepatide 5 mg | Tirzepatide 10 mg | Tirzepatide 15 mg | Semaglutide 1 mg |
|---|---|---|---|---|
| A1c Reduction | −2.01% | −2.24% | −2.30% | −1.86% |
| Weight Loss | −7.6 kg | −9.3 kg | −11.2 kg | −5.7 kg |
All three tirzepatide doses were superior to semaglutide 1 mg for A1c reduction. At the highest dose, patients on tirzepatide lost nearly twice as much weight. Notably, many tirzepatide patients achieved an A1c below 5.7% — a level previously considered unattainable with pharmacotherapy alone — without increased hypoglycemia risk.
One fair criticism: SURPASS-2 compared tirzepatide against semaglutide 1 mg, not the higher 2 mg dose available today. Whether semaglutide 2 mg would narrow the gap is plausible but unproven in a head-to-head trial for diabetes.
Real-World Data
A 2025 real-world study published in PMC tracked HbA1c and weight outcomes in patients with type 2 diabetes starting either drug in clinical practice. At 12 months, tirzepatide was associated with greater A1c reductions (−1.3% vs. −0.9% in treatment-naive patients; P<0.001) and more weight loss (−10.2 kg vs. −6.1 kg; P<0.001) compared to semaglutide — consistent with the clinical trial findings (published 2025, PMC).
Cardiovascular Outcomes
This is where semaglutide currently holds an advantage — though the gap is closing.
Semaglutide: The SELECT Trial
The SELECT trial, published in the NEJM in November 2023, enrolled 17,604 adults with established cardiovascular disease, obesity (BMI 27+), and no diabetes. Over a mean follow-up of 39.8 months, semaglutide 2.4 mg reduced the primary composite endpoint (cardiovascular death, nonfatal heart attack, or nonfatal stroke) by 20% compared to placebo (HR 0.80; 95% CI 0.72–0.90; P<0.001).
This was landmark data. SELECT made Wegovy the first obesity medication ever proven to reduce cardiovascular events — leading to its expanded FDA indication for cardiovascular risk reduction. It fundamentally changed how the medical community views these drugs: not just weight loss tools, but disease-modifying therapies.
Tirzepatide: SURPASS-CVOT
The SURPASS-CVOT trial, published in the NEJM in December 2025, took a different design approach. Because GLP-1 agonists already had proven cardiovascular benefits, the investigators considered a placebo-controlled trial unethical. Instead, they compared tirzepatide (up to 15 mg) against dulaglutide (1.5 mg) — another GLP-1 agonist with known cardiovascular benefits — in 13,000+ patients with type 2 diabetes and established atherosclerotic cardiovascular disease over a median of 4 years (Nicholls et al., NEJM, 2025).
Key findings:
- Primary endpoint (MACE-3): 12.2% with tirzepatide vs. 13.1% with dulaglutide (HR 0.92; P=0.003 for non-inferiority, P=0.09 for superiority — non-inferior but not statistically superior).
- All-cause mortality: 16% reduction with tirzepatide vs. dulaglutide (HR 0.84; 95% CI 0.75–0.94).
- Indirect comparison vs. placebo: A pre-specified analysis using matched data from the REWIND trial estimated tirzepatide would reduce MACE by 28% and all-cause mortality by 39% compared to placebo.
So tirzepatide has cardiovascular benefits — the data supports that clearly. But the comparison isn't apples-to-apples with SELECT. Semaglutide was tested against placebo and showed a clean 20% MACE reduction. Tirzepatide was tested against an active comparator that itself reduces cardiovascular risk, making the absolute benefit harder to quantify directly.
A real-world study published in Nature Medicine in 2025 found that semaglutide and tirzepatide produced similar cardiovascular outcomes in clinical practice for patients with diabetes and elevated cardiovascular risk — suggesting the real-world gap may be smaller than trial designs imply.
Side Effects Comparison
Both drugs cause gastrointestinal side effects. This is not a bug; it's partly the mechanism. Slowing gastric emptying reduces appetite but also causes nausea, especially during dose escalation. Here's how the side effect profiles compare across clinical trials.
Gastrointestinal Side Effects
| Side Effect | Semaglutide | Tirzepatide |
|---|---|---|
| Nausea | 16–20% | 17–22% |
| Diarrhea | 10–12% | 12–17% |
| Vomiting | 6–8% | 6–10% |
| Constipation | 10–14% | 6–11% |
| GI-related discontinuation | 5.6% (SURMOUNT-5) | 2.7% (SURMOUNT-5) |
Data drawn from SURPASS-2, SURMOUNT-5, and individual trial programs.
A few things stand out. The overall GI side effect rates are similar between the two drugs. Both cause nausea in roughly one-fifth of patients, and most episodes are mild to moderate. They peak during dose escalation and tend to resolve as the body adjusts.
One counterintuitive finding from SURMOUNT-5: despite producing more weight loss, tirzepatide actually had a lower rate of GI-related treatment discontinuation (2.7%) than semaglutide (5.6%). Some researchers speculate that GIP receptor activation may partially buffer against GLP-1-driven nausea, though this hypothesis is still being investigated.
Semaglutide tends to cause more constipation, while tirzepatide leans toward more diarrhea — a pattern that has been consistent across multiple trials.
Serious Adverse Events
Serious adverse events are uncommon with both drugs. In SURMOUNT-5, rates were 4.8% for tirzepatide and 3.5% for semaglutide. Both carry warnings about pancreatitis (rare), gallbladder disease, and a theoretical thyroid C-cell tumor risk based on rodent studies (no confirmed human cases).
Both drugs carry a boxed warning regarding thyroid C-cell tumors based on rodent studies, though no causal link has been confirmed in humans to date. Neither drug should be used in patients with a personal or family history of medullary thyroid carcinoma or Multiple Endocrine Neoplasia syndrome type 2.
Gallbladder-related events (gallstones, cholecystitis) occur at slightly elevated rates with both drugs, likely related to rapid weight loss rather than the medications themselves. In SURMOUNT-1, cholelithiasis was reported in about 1.3% of tirzepatide patients vs. 0.3% on placebo. Similar rates have been observed with semaglutide.
Injection site reactions are generally mild with both drugs — redness, itching, or slight swelling at the injection site. These tend to resolve quickly and rarely require treatment changes.
For detailed strategies on managing GI symptoms during treatment, see our guide on how to manage GLP-1 side effects.
Body Composition: The Muscle Loss Question
One concern that gets significant attention — appropriately — is what happens to muscle mass during rapid weight loss on these drugs.
The data shows that lean tissue loss accounts for roughly 25–40% of total weight lost with both medications. In the STEP 1 semaglutide trial, approximately 39% of weight lost came from lean mass. In the SURMOUNT-1 tirzepatide trial, lean mass dropped by 10–11% while fat mass dropped by 33–36% (Look et al., Diabetes, Obesity and Metabolism, 2025).
Some analyses suggest tirzepatide may preserve a slightly higher proportion of lean mass relative to total weight lost — possibly related to GIP's effects on muscle and fat tissue — but this finding isn't definitive yet.
What is clear: resistance training and adequate protein intake (1.2–1.6 g/kg/day, or higher for active individuals) substantially mitigate lean mass loss. A 2025 case series showed that patients combining GLP-1 therapy with structured resistance training 3–5 days per week and high protein intake actually gained lean mass while losing significant body fat (Tinsley & Nadolsky, BMJ Case Reports, 2025).
Several pharmaceutical approaches to preserving muscle during GLP-1 therapy are now in clinical trials, including combinations with myostatin inhibitors like bimagrumab. Next-generation drugs like retatrutide (a triple GIP/GLP-1/glucagon agonist) are also being studied for their body composition effects.
Cost and Insurance Coverage
The practical reality for millions of people comes down to one question: can I afford it? The pricing situation has shifted significantly in 2025–2026, but it remains complicated.
List Prices
Without insurance or discount programs, both drugs carry sticker prices that most people can't sustain:
- Wegovy (semaglutide): ~$1,349–$1,613/month
- Ozempic (semaglutide): ~$935–$1,029/month
- Zepbound (tirzepatide): ~$1,060/month
- Mounjaro (tirzepatide): ~$1,023–$1,095/month
Discount Programs and Self-Pay Options
Both manufacturers now offer significant discounts for self-paying patients:
Novo Nordisk (semaglutide):
- Wegovy and Ozempic: $349/month through direct self-pay programs
- GoodRx introductory pricing: $199/month for first two fills, then $299–$349/month ongoing
- Wegovy pill (oral semaglutide for weight loss): Launched in early 2026
Eli Lilly (tirzepatide):
- Zepbound: $299/month for starting doses, $449/month for higher doses through direct-to-consumer pricing
- Mounjaro: Similar discount structures for self-pay patients
Medicare and Medicaid
A major shift: as of 2026, Medicare will cover Wegovy and Zepbound for obesity with related comorbidities for the first time. The negotiated Medicare price is $245/month with a $50 patient copay. Medicaid programs are gaining access at similar price points. Full rollout is expected through mid-2026 (NPR, November 2025).
Commercial Insurance
This is where it gets frustrating. Coverage for weight loss specifically is declining in many commercial plans heading into 2026:
- Only about 19% of large employers cover GLP-1 drugs for weight loss (2025 data)
- Several major insurers (Blue Cross Blue Shield, Cigna, UnitedHealthcare) have tightened coverage criteria
- Zepbound coverage has dropped: 56% of commercially insured individuals now have no coverage for it
- Both drugs are more consistently covered for type 2 diabetes, though prior authorization requirements are common (~78–81% of the time)
Cost-Effectiveness
A cost-effectiveness analysis published in the Journal of Managed Care & Specialty Pharmacy in 2025 found that the cost per 1% body weight reduction was $985 with tirzepatide vs. $1,845 with semaglutide — making tirzepatide the more cost-effective option per unit of weight lost (JMCP, 2025).
For a broader cost comparison across all available branded options, see our branded GLP-1 drugs comparison.
Which One Is Right for You?
There's no universal answer, but the clinical data and practical considerations point toward different drugs for different situations. Here are the key factors to weigh with your prescriber.
Tirzepatide may be the better fit if:
- Maximizing weight loss is the primary goal. The data is consistent: tirzepatide produces 30–50% more weight loss than semaglutide across every population studied. For someone with a BMI of 40+ or significant obesity-related comorbidities, that additional weight reduction can be clinically meaningful.
- You have type 2 diabetes requiring aggressive glycemic control. Tirzepatide produced A1c reductions of 2.0–2.3% in trials — enough to bring many patients below the normal threshold of 5.7% without increased hypoglycemia.
- You've tried semaglutide and plateaued. There's no published switching trial yet, but clinicians increasingly report that patients who plateau on semaglutide see further weight loss after transitioning to tirzepatide. See our guide on how to transition between GLP-1 medications.
- Cost per pound lost matters to you. At current self-pay pricing, tirzepatide delivers more weight loss per dollar spent.
Semaglutide may be the better fit if:
- You have established cardiovascular disease. SELECT is the only completed placebo-controlled cardiovascular outcomes trial for this drug class in patients with obesity. Semaglutide 2.4 mg reduced major cardiovascular events by 20% — data that tirzepatide can't directly match yet.
- You prefer an oral option. The Wegovy pill (oral semaglutide 25 mg daily) launched in early 2026. Tirzepatide has no oral formulation available yet, though Eli Lilly has one in development.
- Insurance covers it but not tirzepatide. Formulary restrictions vary wildly. Some plans cover Wegovy but not Zepbound, or Ozempic but not Mounjaro. Check your specific plan.
- You tolerated semaglutide well and are getting good results. If you're already on semaglutide, losing weight steadily, and tolerating it without major side effects — there's no automatic reason to switch. The best drug is the one you can take consistently.
Factors that apply equally to both:
- Both require long-term use. Stopping either drug leads to weight regain — the SURMOUNT-4 and STEP 4 withdrawal studies both confirmed this clearly.
- Both work best when combined with dietary changes and physical activity.
- Both require gradual dose escalation over 4–5 months.
- Neither is a first-line treatment for people who haven't tried lifestyle interventions.
The Bottom Line
The head-to-head data is in, and tirzepatide is the more potent weight loss drug. SURMOUNT-5 showed a 20.2% vs. 13.7% weight reduction — a gap that's hard to dismiss. Tirzepatide also outperforms semaglutide on blood sugar control. And despite producing more weight loss, it had fewer GI-related treatment discontinuations in the direct comparison trial.
But "more potent" doesn't automatically mean "better for you." Semaglutide has the strongest cardiovascular outcomes evidence in the class, a proven oral formulation, and a longer track record. For patients with established heart disease, those data points carry real weight.
The good news is that both drugs represent a genuine therapeutic advance. Five years ago, the idea of a weekly injection producing 15–20% sustained weight loss while improving cardiovascular risk factors would have seemed unrealistic. Now clinicians have two proven options — and a growing pipeline that may push the boundaries further.
The right choice depends on your specific health profile, your goals, your insurance situation, and how you respond to treatment. That's a conversation to have with your doctor — armed with the data above.
One final note on what's ahead: the next generation of incretin-based therapies is already in late-stage trials. Eli Lilly's retatrutide — a triple GIP/GLP-1/glucagon receptor agonist — produced nearly 29% weight loss in Phase 3, exceeding even tirzepatide. Oral versions of both semaglutide and tirzepatide are in development or recently approved. Amycretin, survodutide, and other dual and triple agonists are moving through Phase 2 and 3 programs. The field is evolving fast, and the comparison we've drawn here will likely need updating within a year. For now, though, semaglutide and tirzepatide remain the two best-studied, most widely available options.
For a full overview of all branded options currently on the market, see our branded GLP-1 drugs comparison.
This article is for educational purposes only and does not constitute medical advice. Always consult a qualified healthcare provider before starting, stopping, or changing any medication.
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