Wegovy vs Zepbound (semaglutide vs tirzepatide)

Which is better, semaglutide or tirzepatide?

For weight loss alone, tirzepatide wins on head-to-head evidence (SURMOUNT-5 and SURPASS-2). For a patient with established cardiovascular disease and obesity but no diabetes, semaglutide is the only one of the two with a completed cardiovascular outcomes trial in that group and an FDA labeled indication to reduce major adverse cardiovascular events there. Tolerability, cost, and insurance coverage for the specific indication usually decide between them in practice. [1] [2] [5] [6] [7]

How do semaglutide and tirzepatide compare?

Semaglutide and Tirzepatide compared by dimension
Dimension	Semaglutide	Tirzepatide
Head-to-head evidence [1] [2]	Lost 13.7% of body weight at 72 weeks in SURMOUNT-5 (semaglutide 2.4 mg or maximum tolerated dose). Lowered HbA1c by 1.86 points at 40 weeks in SURPASS-2 (1 mg dose).	Lost 20.2% of body weight at 72 weeks in SURMOUNT-5 (tirzepatide 15 mg or maximum tolerated dose). Lowered HbA1c by 2.01 to 2.30 points and weight by 7.6 to 11.2 kg at 40 weeks in SURPASS-2 across 5, 10, and 15 mg doses.
Note: SURMOUNT-5 randomized 751 adults with obesity and no diabetes. SURPASS-2 randomized 1,879 adults with type 2 diabetes on metformin and compared tirzepatide with semaglutide 1 mg, not the 2.4 mg obesity dose.
Placebo-controlled weight loss [3] [4]	14.9% vs 2.4% for placebo at 68 weeks in STEP 1 (1,961 adults with overweight or obesity).	15.0%, 19.5%, and 20.9% at 5, 10, and 15 mg vs 3.1% for placebo at 72 weeks in SURMOUNT-1 (2,539 adults).
Note: Cross-trial comparisons are unreliable; the direct trial (SURMOUNT-5) is the better guide.
Mechanism [6] [7]	Selective GLP-1 receptor agonist.	Dual GIP and GLP-1 receptor agonist.
FDA labeled indications [6] [7] [12] [13]	Wegovy (injection and tablets): chronic weight management (the injection also from age 12), reduction of major adverse cardiovascular events in adults with established cardiovascular disease and obesity or overweight, and, for the injection, noncirrhotic MASH with moderate to advanced fibrosis. Ozempic: type 2 diabetes, cardiovascular risk reduction in type 2 diabetes, and kidney outcomes in type 2 diabetes with chronic kidney disease. Rybelsus and Ozempic tablets: type 2 diabetes.	Zepbound: chronic weight management in adults and moderate to severe obstructive sleep apnea in adults with obesity. Mounjaro: type 2 diabetes in adults and children 10 and older, and reduction of major adverse cardiovascular events in adults with type 2 diabetes at high cardiovascular risk.
Cardiovascular outcomes [5] [7] [12] [14] [15]	SELECT: 20% relative reduction in major adverse cardiovascular events vs placebo (hazard ratio 0.80) in 17,604 adults with cardiovascular disease and overweight or obesity without diabetes. SUSTAIN-6: hazard ratio 0.74 in type 2 diabetes.	No completed cardiovascular outcomes trial in obesity without diabetes, and the Zepbound label has no cardiovascular indication. In type 2 diabetes with cardiovascular disease, SURPASS-CVOT (13,165 adults) found tirzepatide noninferior to dulaglutide (hazard ratio 0.92), and the Mounjaro label now carries a cardiovascular risk reduction indication.
Common side effects [2] [6] [7]	Nausea, diarrhea, vomiting, constipation, abdominal pain, headache, fatigue. Rates are highest during dose escalation.	Nausea, diarrhea, vomiting, constipation, abdominal pain, dyspepsia, injection site reactions, fatigue. In SURPASS-2 gastrointestinal events were similar in kind to semaglutide and dose dependent.
Note: Both labels carry a boxed warning for thyroid C-cell tumors seen in rodents and are contraindicated with a personal or family history of medullary thyroid carcinoma or MEN 2. Both warn about pancreatitis, gallbladder disease, hypoglycemia with insulin or sulfonylureas, and delayed gastric emptying.
Regulatory status [6] [7] [8]	FDA approved: Ozempic (2017), Rybelsus (2019), Wegovy (2021). Compounding allowance ended after the shortage was resolved on February 21, 2025 (503A grace period ended April 22, 2025).	FDA approved: Mounjaro (May 2022), Zepbound (November 2023). Compounding allowance ended after the shortage was resolved on December 19, 2024 (503A grace period ended February 18, 2025).
WADA status [9]	Not on the WADA Prohibited List.	Not on the WADA Prohibited List.
Note: Neither drug is prohibited in sport, but athletes should confirm any co-prescribed agent against the current list.
Route and dosing frequency [6] [7] [12] [13]	Subcutaneous injection once weekly (Wegovy or Ozempic pen). Once daily tablets: Wegovy tablets for weight management, and Ozempic tablets and Rybelsus for type 2 diabetes.	Subcutaneous injection once weekly (Zepbound or Mounjaro single-dose pen, single-dose vial, multi-dose vial, or KwikPen). No oral form.
Label dose escalation [6] [7] [12] [13]	Wegovy injection: 0.25 mg weekly for 4 weeks, then 0.5, 1, and 1.7 mg at 4-week steps; 2.4 mg (or 1.7 mg) maintenance, with an optional increase to a 7.2 mg maximum for weight reduction in adults. Ozempic: 0.25 mg, then 0.5 mg, with optional 1 mg and 2 mg steps.	Zepbound and Mounjaro: 2.5 mg weekly for 4 weeks, then 5 mg, with optional 2.5 mg increases after at least 4 weeks up to a 15 mg maximum. Zepbound maintenance is 5, 10, or 15 mg for weight and 10 or 15 mg for sleep apnea.
Typical cost [10] [11]	Wegovy list price 1,349.02 USD per month and Ozempic 1,027.51 USD. Manufacturer self-pay: Wegovy tablets from 149 USD per month and the Wegovy pen 349 USD (399 USD at 7.2 mg); as little as 25 USD with commercial coverage and the savings offer.	Zepbound list price up to 1,086.37 USD per fill and Mounjaro 1,112.16 USD. Manufacturer self-pay Zepbound vials or KwikPen: 299 USD at 2.5 mg up to 699 USD at 10 mg and above; as little as 25 USD with commercial coverage and a savings card.
Note: Prices checked 2026-09-22 on manufacturer pages and change often; see the cost pages for each drug and channel.

Evidence grade and regulatory status

Pulled from each peptide’s own record, so it stays in step with the peptide pages.

Semaglutide and Tirzepatide: grade, status, and cost
Attribute	Semaglutide	Tirzepatide
Class	GLP-1 receptor agonist (31 amino acid analog of human GLP-1, acylated for once weekly dosing)	Dual GIP and GLP-1 receptor agonist (39 amino acid peptide, acylated for once weekly dosing)
What it is	FDA approved GLP-1 agonist with about 15% average weight loss in a 68 week RCT and proven cardiovascular benefit.	FDA approved weekly GIP and GLP-1 drug with 20.9% average weight loss at 15 mg in a 72 week randomized trial; beat semaglutide head to head.
Evidence	Evidence: Human RCT evidence	Evidence: Human RCT evidence
FDA status	Regulatory: FDA approved	Regulatory: FDA approved
Compounding	FDA approved products (Ozempic 2017, Rybelsus 2019, Wegovy 2021). FDA removed semaglutide from the drug shortage list on February 21, 2025; compounding by 503A pharmacies had to stop by April 22, 2025 and by 503B outsourcing facilities by May 22, 2025, except for a documented patient specific clinical need. FDA has warned about unapproved compounded and counterfeit GLP-1 products and salt forms (semaglutide sodium, semaglutide acetate) that are not the approved active ingredient. On April 30, 2026 FDA proposed not to include semaglutide on the 503B bulks list; that proposal was not final as of September 2026. Adding a vitamin such as B12 or niacinamide does not by itself make a compounded GLP-1 different from the approved drug. Under FDA's April 1, 2026 policy update, such a combination may be treated as essentially a copy when the strengths are within 10% of approved products and the route is the same, unless a prescriber documents a real difference for the individual patient. A September 2026 FDA warning letter applied this to semaglutide and tirzepatide vitamin combinations, said high production volume suggested the claimed differences were a pretext, and questioned significant-difference statements picked from preset menus on prescribing platforms.	FDA approved products (Mounjaro May 2022, Zepbound November 2023). FDA declared the tirzepatide shortage resolved on December 19, 2024; compounding by 503A pharmacies had to stop by February 18, 2025 and by 503B outsourcing facilities by March 19, 2025, except for a documented patient specific clinical need. FDA has warned about unapproved compounded and counterfeit tirzepatide products. On April 30, 2026 FDA proposed not to include tirzepatide on the 503B bulks list; that proposal was not final as of September 2026. Adding a vitamin such as B12 or niacinamide does not by itself make a compounded GLP-1 different from the approved drug. Under FDA's April 1, 2026 policy update, such a combination may be treated as essentially a copy when the strengths are within 10% of approved products and the route is the same, unless a prescriber documents a real difference for the individual patient. A September 2026 FDA warning letter applied this to semaglutide and tirzepatide vitamin combinations, said high production volume suggested the claimed differences were a pretext, and questioned significant-difference statements picked from preset menus on prescribing platforms.
WADA	WADA: Not WADA prohibited	WADA: Not WADA prohibited
Routes	Subcutaneous injection once weekly (Ozempic, Wegovy), Oral tablet once daily (Wegovy tablets, Ozempic tablets, Rybelsus)	Subcutaneous injection once weekly (pen or single dose vial)
Typical cost	Manufacturer list price is 1,349.02 USD per month for Wegovy and 1,027.51 USD for Ozempic (checked 2026-09-22), falling to 675 USD for both on January 1, 2027. Manufacturer self-pay prices run 149 to 499 USD per month by product and dose, with the Wegovy pen at 349 USD. With commercial insurance the manufacturer savings offer can bring a covered prescription to 25 USD per month, and eligible Medicare Part D enrollees pay 50 USD per month for Wegovy under the Medicare GLP-1 Bridge (July 2026 to December 2027). A 2024 study found compounded semaglutide at a median 231 USD for the first month during the shortage; compounding is now limited to patient specific needs.	Manufacturer list price is up to 1,086.37 USD per fill for Zepbound and 1,112.16 USD for Mounjaro (checked 2026-09-22). Manufacturer self-pay Zepbound vials and KwikPen cost 299 USD per month at 2.5 mg, 399 at 5 mg, 499 at 7.5 mg, and 699 at 10 mg and above, with a 449 USD on-time refill offer for the 7.5 mg and higher KwikPen through 2026. With commercial insurance a savings card can bring a covered prescription to 25 USD, and eligible Medicare Part D enrollees pay 50 USD per month for the Zepbound KwikPen under the Medicare GLP-1 Bridge (July 2026 to December 2027). A study published in 2025 found compounded tirzepatide advertised at a median 330 USD for the first month during the shortage; compounding is now limited to patient specific needs.
Last verified	Sep 27, 2026	Sep 27, 2026

Wegovy vs Zepbound: weight loss in the head-to-head trial

Direct comparisons of Semaglutide and Tirzepatide
Study	Design and population	Outcome	Grade
Tirzepatide as compared with semaglutide for the treatment of obesity (SURMOUNT-5)2025 PMID 40353578	Phase 3b open-label randomized controlled trial, 72 weeksn = 751 Adults with obesity, or overweight plus at least one weight-related complication, without type 2 diabetes	Mean weight change 20.2% with tirzepatide vs 13.7% with semaglutide at 72 weeks	Evidence: Human RCT evidence
Tirzepatide versus semaglutide once weekly in patients with type 2 diabetes (SURPASS-2)2021 PMID 34170647	Phase 3 open-label randomized controlled trial, 40 weeksn = 1,879 Adults with type 2 diabetes inadequately controlled on metformin	HbA1c reduction 2.01, 2.24, and 2.30 points with tirzepatide 5, 10, and 15 mg vs 1.86 with semaglutide 1 mg; weight loss 7.6, 9.3, and 11.2 kg vs 5.7 kg	Evidence: Human RCT evidence

What do semaglutide and tirzepatide cost?

Typical cost of Semaglutide and Tirzepatide
Dimension	Semaglutide	Tirzepatide
Typical cost	$149 to $1,349 per month	$275 to $1,112 per month
Price detail	Semaglutide price by channel	Tirzepatide price by channel

Where a price index exists, the range is the cash price per month across branded, compounded, and telehealth channels, without insurance. The cost pages give each channel separately with its sources. Otherwise the typical cost from the peptide record is shown. Legal access depends on your state: see peptide legality by state.

Frequently asked questions

Wegovy vs Zepbound: which causes more weight loss?

Zepbound. In SURMOUNT-5, the direct comparison in 751 adults with obesity and no diabetes, tirzepatide (Zepbound's ingredient) produced 20.2% weight loss at 72 weeks versus 13.7% with semaglutide (Wegovy's ingredient), each at the maximum tolerated dose up to 15 mg and 2.4 mg. It is the only head-to-head obesity trial of the two. [1]

Ozempic vs Mounjaro: which is better for type 2 diabetes?

On blood sugar and weight, Mounjaro. In SURPASS-2, tirzepatide 5, 10, and 15 mg lowered HbA1c by 2.01 to 2.30 percentage points versus 1.86 with semaglutide 1 mg over 40 weeks, and weight by 7.6 to 11.2 kg versus 5.7 kg; the trial did not test Ozempic's 2 mg dose. Ozempic has the longer heart record in type 2 diabetes (SUSTAIN-6) and a kidney outcomes indication, while tirzepatide was noninferior to dulaglutide for heart events in SURPASS-CVOT. [2] [13] [14] [15]

Wegovy vs Mounjaro: what is the difference?

They are different molecules with different labels. Wegovy is semaglutide, labeled for weight management, cardiovascular risk reduction, and MASH. Mounjaro is tirzepatide, labeled for type 2 diabetes and cardiovascular risk reduction in type 2 diabetes, not for weight management. Tirzepatide's weight management label is Zepbound, and in SURMOUNT-5 tirzepatide produced 20.2% weight loss versus 13.7% with semaglutide. [1] [6] [7] [12]

Is semaglutide better for the heart?

In people with obesity but no diabetes, yes on current evidence: SELECT showed a 20% relative reduction in major adverse cardiovascular events with semaglutide, and Wegovy carries an FDA indication for that use, while Zepbound has none. In type 2 diabetes the gap is smaller: SURPASS-CVOT found tirzepatide noninferior to dulaglutide (hazard ratio 0.92), and the Mounjaro label now includes cardiovascular risk reduction in type 2 diabetes. [5] [6] [7] [12] [14]

Do they have different side effects?

The side effect profiles are largely the same: nausea, vomiting, diarrhea, and constipation that peak during dose escalation, plus the same boxed warning about thyroid C-cell tumors and the same contraindication for medullary thyroid carcinoma or MEN 2. In SURPASS-2 gastrointestinal events were similar in kind between the two drugs. [2] [6] [7]

Can I switch from Wegovy to Zepbound?

Switching happens in practice but neither label includes a switching protocol, and neither SURMOUNT-5 nor SURPASS-2 studied it. The labels start tirzepatide at 2.5 mg weekly regardless of prior GLP-1 dose. Talk to the prescriber about timing and escalation rather than following an online schedule. [6] [7]

Conditions studied

From the blog

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Berberine, fiber, and probiotics sold as GLP-1 boosters are not GLP-1 drugs. Here is the human evidence for each ingredient, graded, and how it compares with semaglutide and tirzepatide.
Microdosing GLP-1s and tirzepatide: what the evidence says
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Peptide before and after: trial results vs marketing photos
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Peptides for weight loss, ranked by human evidence
Tirzepatide, semaglutide, and liraglutide lead on human trials. Retatrutide is trial-only, and AOD-9604 and 5-amino-1MQ are animal-only. Ranking, legal status, and dated prices.

Sources

Numbered citations above point to these primary sources. PubMed entries link to the indexed abstract.

Cite this page

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APA style: PeptideAgent. (2026, September 23). Semaglutide vs tirzepatide: evidence, cost, and legality. https://peptideagent.ai/compare/semaglutide-vs-tirzepatide
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Wegovy vs Zepbound and Ozempic vs Mounjaro (semaglutide vs tirzepatide)

The short answer