Comparison

SemaglutideTirzepatide

Semaglutide (Ozempic, Wegovy) and Tirzepatide (Mounjaro, Zepbound) are the two FDA-approved GLP-1 peptides that have dominated metabolic research since 2021. The key difference is mechanism — Semaglutide activates only GLP-1, while Tirzepatide is a dual GIP/GLP-1 agonist.

Spec	A Semaglutide	B Tirzepatide
Mechanism	GLP-1 mono agonist	GIP + GLP-1 dual agonist
Manufacturer	Novo Nordisk	Eli Lilly
Weight loss (clinical)	14.9% / 68 weeks (STEP 1)	22.5% / 72 weeks (SURMOUNT-1)
Half-life	~7 days	~5 days
Dosing	1× weekly s.c.	1× weekly s.c.
FDA status	Approved 2017 (diabetes), 2021 (obesity)	Approved 2022 (diabetes), 2023 (obesity)
Open literature	STEP 1-8, SUSTAIN series	SURMOUNT 1-5, SURPASS 1-5

Choose A when

Semaglutide

Longer history, larger published literature base, lower cycle cost. Established standard.

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Choose B when

Tirzepatide

Stronger SURMOUNT-1 numbers, added GIP component for thermogenesis and lipid metabolism. Premium option.

See full profile

Verdict

Tirzepatide wins on absolute weight loss; Semaglutide remains more studied and cheaper. Choice depends on which literature you follow and your cycle budget.

Frequently asked

What people ask

Is Tirzepatide stronger than Semaglutide?

In SURPASS-2, Tirzepatide outperformed Semaglutide on HbA1c and weight — −2.46% vs −1.86%. SURMOUNT-1 saw 22.5% weight loss vs Semaglutide's 14.9% (STEP 1). The two regimens aren't directly equivalent in clinical comparison but at matched doses Tirzepatide leads on absolute numbers.

Can Semaglutide and Tirzepatide be stacked?

No. Both activate GLP-1R with heavy overlap — stacking offers no extra benefit but cumulative GI side effects (nausea) are likely. Pick one.

Other comparisons

Keep exploring

Semaglutide vs Retatrutide

Tirzepatide vs Retatrutide

BPC-157 vs TB-500

Ipamorelin vs CJC-1295

Last reviewed: 6 May 2026by PeptidLabs Editorial

Comparison

SemaglutideTirzepatide

Spec	A Semaglutide	B Tirzepatide
Mechanism	GLP-1 mono agonist	GIP + GLP-1 dual agonist
Manufacturer	Novo Nordisk	Eli Lilly
Weight loss (clinical)	14.9% / 68 weeks (STEP 1)	22.5% / 72 weeks (SURMOUNT-1)
Half-life	~7 days	~5 days
Dosing	1× weekly s.c.	1× weekly s.c.
FDA status	Approved 2017 (diabetes), 2021 (obesity)	Approved 2022 (diabetes), 2023 (obesity)
Open literature	STEP 1-8, SUSTAIN series	SURMOUNT 1-5, SURPASS 1-5

Choose A when

Semaglutide

Longer history, larger published literature base, lower cycle cost. Established standard.

See full profile

Choose B when

Tirzepatide

Stronger SURMOUNT-1 numbers, added GIP component for thermogenesis and lipid metabolism. Premium option.

See full profile

Verdict

Tirzepatide wins on absolute weight loss; Semaglutide remains more studied and cheaper. Choice depends on which literature you follow and your cycle budget.

Frequently asked

What people ask

Is Tirzepatide stronger than Semaglutide?

Can Semaglutide and Tirzepatide be stacked?

No. Both activate GLP-1R with heavy overlap — stacking offers no extra benefit but cumulative GI side effects (nausea) are likely. Pick one.

Other comparisons

Keep exploring

Semaglutide vs Retatrutide

Tirzepatide vs Retatrutide

BPC-157 vs TB-500

Ipamorelin vs CJC-1295

Last reviewed: 6 May 2026by PeptidLabs Editorial