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/ comparison

Semaglutide
vs
Tirzepatide

Side-by-side comparison of mechanism, research, dosing, side effects, and pricing.

peptide

Semaglutide

FDA-approved GLP-1 agonist. The most-studied weight management peptide.

Cheapest
$77.60
3mg at Ascension Peptides
See Semaglutide →
peptide

Tirzepatide

Dual receptor agonist. Outperforms semaglutide in head-to-head trials.

Cheapest
$85.93
5mg at Ascension Peptides
See Tirzepatide →
/ research scoring

Research base

Semaglutide
Research Maturity★★★★★
Evidence Strength★★★★★

200+ clinical trials. Strongest evidence base for weight research peptides. Works as researched.

Tirzepatide
Research Maturity★★★★★
Evidence Strength★★★★★

FDA approved. Phase 3 trials show superior metabolic effects vs single-receptor agonists.

/ mechanism

How they work

Semaglutide

GLP-1 receptor agonist. Decreases appetite, slows gastric emptying, improves insulin sensitivity.

Tirzepatide

Activates both GLP-1 and GIP receptors. Dual-pathway stimulation.

/ research dosing

Protocols compared

Semaglutide
Range: 0.25 → 0.5 → 1.0 → 1.7 → 2.4 mg/week (FDA titration)
Frequency: Once weekly subcutaneous
Route: Subcutaneous abdomen, thigh, or upper arm
Standard FDA titration schedule for Wegovy. Each dose held minimum 4 weeks before increase. GI side effects (nausea, constipation) most pronounced in first 2 weeks of each new dose. If missing dose: take within 5 days, otherwise skip to next scheduled week.
Tirzepatide
Range: 2.5 → 5 → 7.5 → 10 → 12.5 → 15 mg/week (FDA titration)
Frequency: Once weekly subcutaneous
Route: Subcutaneous abdomen, thigh, or upper arm
Standard FDA titration for Mounjaro/Zepbound. Same molecule, same dosing ladder. Each step held 4 weeks minimum. If missing dose: take if >72 hours until next dose; otherwise skip. Dual GLP-1/GIP agonist — typically better GI tolerance than retatrutide at equivalent weight-loss efficacy.
/ side effects & timeline

What to expect

Semaglutide
Side effects

Common: nausea (30%), GI adjustment. Usually resolve over time.

Timeline

2-4 weeks for appetite suppression, 12+ weeks for significant changes

Tirzepatide
Side effects

Common: GI adjustment. Well-tolerated overall.

Timeline

Effects within 2-4 weeks

/ pricing

Price comparison

Semaglutide
Lowest price$77.60 (3mg)
Min $/mg$10.47/mg
Avg $/mg$31.11/mg
Max $/mg$67.79/mg
Tirzepatide
Lowest price$85.93 (5mg)
Min $/mg$7.90/mg
Avg $/mg$20.50/mg
Max $/mg$45.19/mg
/ which to pick

The honest verdict

Pick Semaglutide if: Strong standalone evidence. Most clinical trials test it alone.

Pick Tirzepatide if: Highly effective alone. Dual-agonist mechanism is its key feature.

Why not both? Some researchers run them together. Check our Interaction Matrix to see if these compounds synergize or work independently.

FOR RESEARCH USE ONLY. Both compounds are intended for laboratory research and not for human consumption.