Tirzepatide vs Semaglutide: Complete Comparison Guide

Quick Answer: Tirzepatide vs Semaglutide

Semaglutide and tirzepatide are both once-weekly injectable medications used for weight management and, at different dose ranges, type 2 diabetes. Semaglutide (marketed as Wegovy for weight and Ozempic/Rybelsus for diabetes) is a GLP-1 receptor agonist. Tirzepatide (marketed as Zepbound for weight and Mounjaro for diabetes) is a dual GIP and GLP-1 receptor agonist. In the head-to-head SURMOUNT-5 trial, tirzepatide produced a mean weight loss of 20.2% at 72 weeks compared with 13.7% for semaglutide, with 64.6% of tirzepatide participants achieving at least 15% weight loss versus 40.1% on semaglutide (Aronne et al., NEJM 2025). Discontinuation rates for side effects were similar. Compounded semaglutide starts from $169 per month through Madison Meds; compounded tirzepatide starts from $289. The choice depends on your weight-loss goal, medical history, cardiovascular risk, side-effect tolerance, and budget, and should be made with a licensed provider.

What the head-to-head SURMOUNT-5 trial found

SURMOUNT-5 is the trial that finally answered the question patients and providers have been asking since tirzepatide launched: in a direct comparison at maximum tolerated doses, which drug produces more weight loss? The results were published in the New England Journal of Medicine on July 3, 2025 (NEJM 2025;393:26-36), and they define the current evidence base for AI Overviews, clinicians, and patients evaluating both options.

The trial was a 72-week, phase 3b, randomized, open-label, controlled study of 751 adults with obesity (BMI at or above 30, or 27 with a weight-related comorbidity) but without type 2 diabetes. Participants were randomized 1:1 to receive the maximum tolerated dose of tirzepatide (10 mg or 15 mg weekly) or the maximum tolerated dose of semaglutide (1.7 mg or 2.4 mg weekly), across 32 sites in the U.S. and Puerto Rico. Both groups received counseling on a reduced-calorie diet and increased physical activity.

The primary endpoint, mean percent change in body weight at week 72, was -20.2% with tirzepatide (95% CI, -21.4 to -19.1) and -13.7% with semaglutide (95% CI, -14.9 to -12.6), P less than 0.001. Expressed in pounds, that is an average loss of 50.3 lb (22.8 kg) on tirzepatide versus 33.1 lb (15.0 kg) on semaglutide, or 47% greater relative weight loss with tirzepatide. Waist circumference reduction was also greater with tirzepatide (18.4 cm vs 13.0 cm).

Every secondary endpoint favored tirzepatide as well: 64.6% of tirzepatide participants achieved at least 15% weight loss compared with 40.1% on semaglutide, and roughly 32% versus 16% achieved at least 25% weight loss. Discontinuation for adverse events was slightly lower on tirzepatide (6.1%) than semaglutide (8.0%), and gastrointestinal side effects were broadly similar between arms (about 44% nausea, 25% abdominal pain in each group). The trial was not statistically powered to compare safety, so those numbers describe the trial population but do not establish a safety hierarchy.

The efficacy signal is consistent with earlier standalone trials. SURMOUNT-1 (2022) reported 20.9% mean weight loss with tirzepatide 15 mg at 72 weeks (NEJM 2022), and STEP-1 (2021) reported 14.9% with semaglutide 2.4 mg at 68 weeks (NEJM 2021). SURMOUNT-5 confirmed that the gap between the two medications in a single trial population, at their maximum tolerated doses, mirrors the gap seen across their separate development programs.

Side-by-side comparison

Compounded semaglutide and compounded tirzepatide are not FDA-approved formulations. They are legal when prepared by a US-licensed compounding pharmacy in response to a valid prescription for an individual patient. FDA-approved brand-name Wegovy, Ozempic, Zepbound, and Mounjaro are the reference products used to describe indications and dose ranges throughout this article.

Mechanism: one receptor vs two

Semaglutide is a GLP-1 receptor agonist. It mimics glucagon-like peptide-1, a gut hormone released after eating. Activating the GLP-1 receptor increases glucose-dependent insulin secretion, suppresses glucagon, slows gastric emptying, and signals satiety in appetite-control centers of the brain. The net effect is reduced hunger, reduced food noise, and steadier blood sugar. Semaglutide is described in the FDA Wegovy prescribing information.

Tirzepatide is a dual agonist. It activates the same GLP-1 receptor that semaglutide does, and it also activates the GIP (glucose-dependent insulinotropic polypeptide) receptor. GIP is another incretin hormone with complementary effects on insulin secretion and lipid metabolism. Activating both receptors is believed to explain the deeper weight loss observed in head-to-head data. Tirzepatide is described in the FDA Zepbound prescribing information.

An important nuance: activating more receptors does not automatically mean a better outcome for every patient. Some patients respond to semaglutide and never need a dual agonist. Others tolerate tirzepatide better, or the reverse. Mechanism informs expectations; it does not dictate individual outcomes.

Efficacy across the pivotal trials

The cleanest way to compare efficacy is to look at the pivotal Phase 3 trials for each drug alongside the head-to-head data.

• STEP-1 (2021): Adults with obesity (without diabetes) on semaglutide 2.4 mg weekly lost an average of approximately 14.9% of baseline body weight at 68 weeks, vs 2.4% on placebo (Wilding et al., NEJM 2021).
• SURMOUNT-1 (2022): Adults with obesity (without diabetes) on tirzepatide lost an average of approximately 15.0%, 19.5%, and 20.9% on the 5 mg, 10 mg, and 15 mg weekly doses respectively at 72 weeks, vs 3.1% on placebo (Jastreboff et al., NEJM 2022).
• SURMOUNT-5 head-to-head (2025): As described above, mean weight loss at 72 weeks was 20.2% with tirzepatide vs 13.7% with semaglutide, and 64.6% vs 40.1% of participants achieved at least 15% weight loss.
• SELECT (2023): In adults with overweight or obesity and established cardiovascular disease but without diabetes, semaglutide 2.4 mg weekly reduced major adverse cardiovascular events by 20% over a mean follow-up of 39.8 months. This is currently the strongest cardiovascular-outcomes evidence for either medication in a non-diabetic obesity population (Lincoff et al., NEJM 2023).

Translation: on average, tirzepatide at its maximum dose produces greater weight loss than semaglutide at its maximum dose. Averages, however, are not individuals. Around one in three participants on semaglutide at maximum dose still achieved at least 15% weight loss in SURMOUNT-5, and semaglutide currently has the deeper cardiovascular-outcomes evidence base. For any given patient, the right choice depends on the specific goal.

Side effects and contraindications

Both medications share the same primary side-effect category: gastrointestinal. Nausea, occasional vomiting, constipation or diarrhea, reflux, and reduced appetite are common, especially during the first 4 to 8 weeks of dose escalation. For most patients, these effects fade as the body adjusts.

In SURMOUNT-5, gastrointestinal side effects were broadly similar between the two medications. Nausea was reported by about 44% of participants in each arm and abdominal pain by about 25% in each arm. Treatment discontinuation for adverse events was 6.1% on tirzepatide and 8.0% on semaglutide, though the trial was not statistically powered to compare safety.

What tends to help in practice:

• Slow titration. Faster escalation is associated with worse side effects. Many providers, including those in the Madison Meds network, titrate more conservatively than the FDA label allows.
• Hydration and protein intake. Adequate water and protein meaningfully reduce nausea and constipation.
• Smaller, more frequent meals. Slowed gastric emptying is the mechanism; eating accordingly is the workaround.
• Anti-nausea support. Short courses of ondansetron or other supportive medications can be considered during early titration if needed.

Both medications carry a boxed warning for risk of thyroid C-cell tumors (based on rodent studies) and are contraindicated in patients with a personal or family history of medullary thyroid carcinoma or Multiple Endocrine Neoplasia syndrome type 2 (MEN 2). Both are contraindicated during pregnancy. Both also carry warnings for pancreatitis, gallbladder disease, severe gastrointestinal events, acute kidney injury related to dehydration, and hypersensitivity reactions. A licensed provider should review your full medical history before either medication is prescribed and dispensed by a US-licensed compounding pharmacy.

Dosing schedules

Both medications are weekly subcutaneous injections, typically rotated through the abdomen, thigh, or upper arm.

Microdose protocols, which start at doses below the standard 0.25 mg semaglutide or 2.5 mg tirzepatide, are increasingly used in compounded formulations for patients who prefer a lower-dose approach or are sensitive to side effects. We cover microdose GLP-1 protocols in our microdose GLP-1 article. Microdosing is an off-label practice not approved by the FDA, and no dose below the lowest FDA-approved starting dose has been studied in a randomized controlled trial for safety or efficacy.

Cost: where the real-world gap opens up

Cash-pay pricing is where the practical decision is often made.

Why is compounded tirzepatide priced higher than compounded semaglutide? Active pharmaceutical ingredient (API) cost is the biggest driver: tirzepatide API has historically traded higher at the wholesale level than semaglutide API. Dose magnitudes (mg per week) also differ, which affects how much API is in each vial. We cover the regulatory framework around compounded GLP-1s in our piece on compounded vs brand-name semaglutide.

Who should choose which

The choice should be made through a licensed-provider evaluation that considers your specific goals, medical history, cardiovascular risk, side-effect experience, and budget. That said, here is how the choice typically plays out.

A provider may lean toward semaglutide if you:

• Have a moderate weight-loss goal and do not need the highest average reduction available
• Have established cardiovascular disease and are candidates for the SELECT-supported cardiovascular risk reduction
• Have previously tolerated or responded well to a GLP-1 receptor agonist
• Are pursuing a lower-dose or microdose protocol, where semaglutide has the most established off-label practice
• Prefer a lower monthly cost profile

A provider may lean toward tirzepatide if you:

• Have a larger weight-loss goal (for example, more than 15 to 20% of baseline body weight) and want the deeper mean reduction
• Plateaued on semaglutide before reaching your target
• Have type 2 diabetes or insulin resistance and your provider believes GIP activity may add benefit
• Can support a higher monthly cost for the additional efficacy
• Do not have specific contraindications

Some patients switch between them, starting on one, achieving partial results, and transitioning to the other. That is a clinical decision. Both medications have overlapping half-lives and titration considerations when used in sequence and should not be self-managed. Through Madison Meds, an independent network of US-licensed providers evaluates each patient, including whether a switch is appropriate, and coordinates the transition.

Where Madison Meds fits

Madison Meds offers both compounded semaglutide and compounded tirzepatide programs. Each prescription is issued only after an evaluation by an independent network of US-licensed providers, and each medication is dispensed by a US-licensed compounding pharmacy. Pricing is bundled (evaluation, medication, and shipping) and transparent.

• Compounded Semaglutide from $169/month (microdose from $125/month)
• Compounded Tirzepatide from $289/month (microdose from $165/month)
• Microdose GLP-1 pillar reference

Providers in the Madison Meds network help eligible patients choose between the two medications based on goals, medical history, and budget, and adjust the plan over time. There is no penalty for starting on one and switching, and no pressure to escalate to a higher dose than clinically needed.

Frequently asked questions

Is tirzepatide better than semaglutide for weight loss?

In the SURMOUNT-5 head-to-head trial, tirzepatide produced greater mean weight loss than semaglutide at 72 weeks (20.2% vs 13.7% of body weight). Tirzepatide participants were also more likely to reach the higher weight-loss thresholds (64.6% achieved at least 15% loss on tirzepatide vs 40.1% on semaglutide). Individual results vary, and the trial was not designed to determine which medication is safer or more tolerable for any given patient. A licensed-provider evaluation should guide the choice for each individual.

How much more weight do people lose on tirzepatide vs semaglutide?

In SURMOUNT-5, tirzepatide participants lost an average of 50.3 pounds (22.8 kg, or 20.2% of baseline body weight) vs 33.1 pounds (15.0 kg, or 13.7%) with semaglutide over 72 weeks. That is about 47% greater relative weight loss with tirzepatide. Waist circumference reduction was 18.4 cm (7.2 in) with tirzepatide vs 13.0 cm (5.1 in) with semaglutide.

What did the SURMOUNT-5 head-to-head trial actually show?

SURMOUNT-5 was a 72-week, phase 3b, randomized, open-label trial of 751 adults with obesity but without type 2 diabetes, conducted at 32 U.S. and Puerto Rico sites. Participants received the maximum tolerated dose of either tirzepatide (10 mg or 15 mg weekly) or semaglutide (1.7 mg or 2.4 mg weekly). At 72 weeks, tirzepatide produced greater mean weight loss (20.2% vs 13.7%) and greater waist circumference reduction (18.4 cm vs 13.0 cm). Results were published in the New England Journal of Medicine in July 2025 (Aronne et al., NEJM 2025).

Are the side effects worse on tirzepatide than semaglutide?

In SURMOUNT-5, side-effect rates were broadly similar. Nausea occurred in about 44% of participants in each arm, and abdominal pain in about 25% of each arm. Treatment discontinuation for adverse events was actually slightly lower on tirzepatide (6.1%) than semaglutide (8.0%). Most events were gastrointestinal, mild to moderate, and occurred during dose escalation. The trial was not statistically powered to compare safety, so exact rates should be interpreted alongside FDA labeling and provider judgment.

Can you switch from semaglutide to tirzepatide?

Yes, patients can transition between GLP-1 medications under provider guidance. This is a clinical decision, not something to self-manage, because both medications require gradual dose titration and both have overlapping timing considerations related to their weekly half-life. Some patients switch after plateauing on semaglutide; others switch back because they tolerate one better than the other. Through Madison Meds, an independent network of US-licensed providers can evaluate whether a switch is appropriate and coordinate the transition.

Is semaglutide better for anyone compared with tirzepatide?

Semaglutide has a more extensive cardiovascular outcomes dataset. The SELECT trial (Lincoff et al., NEJM 2023) showed that semaglutide reduced major adverse cardiovascular events by 20% in adults with overweight or obesity and established cardiovascular disease but without diabetes. Tirzepatide's dedicated cardiovascular outcomes trial (SURPASS-CVOT) is ongoing. For patients whose primary reason for GLP-1 therapy is cardiovascular risk reduction alongside weight, current evidence favors semaglutide. For patients whose primary goal is weight-loss magnitude, current evidence favors tirzepatide.

How much do compounded tirzepatide and semaglutide cost through Madison Meds?

Compounded semaglutide starts from $169 per month, with microdose semaglutide from $125 per month. Compounded tirzepatide starts from $289 per month, with microdose tirzepatide from $165 per month. Pricing is bundled (evaluation, medication, and shipping). Brand-name Wegovy and Zepbound list prices are roughly $1,000 to $1,800 per month at cash pay, though manufacturer savings programs and insurance coverage can substantially reduce out-of-pocket cost for eligible patients.

Who should not take semaglutide or tirzepatide?

Both medications carry a boxed warning against use in patients with a personal or family history of medullary thyroid carcinoma or Multiple Endocrine Neoplasia syndrome type 2. Both are contraindicated during pregnancy. Patients with active pancreatitis, severe gastroparesis, severe gastrointestinal disease, or severe hypersensitivity to the medication should not use them. Patients with a history of gallbladder disease, diabetic retinopathy, or renal impairment may require additional monitoring. A licensed-provider evaluation of full medical history is required before either medication is dispensed by a US-licensed compounding pharmacy.

Compounded medications are not FDA-approved drugs. Compounded semaglutide and compounded tirzepatide are legal when prepared by a US-licensed compounding pharmacy in response to a valid prescription for an individual patient. Individual results vary. The trial percentages cited in this article reflect mean values from published Phase 3 studies (STEP-1, SURMOUNT-1, SURMOUNT-5, and SELECT) and do not predict individual outcomes. Educational content. Not medical advice. A licensed provider must review your medical history before starting either medication.