Tirzepatide is a first-in-class dual GIP and GLP-1 receptor agonist developed by Eli Lilly, FDA-approved for type 2 diabetes (Mounjaro) and chronic weight management (Zepbound) including severe obstructive sleep apnea in adults with obesity. It is a 39-amino-acid peptide with a C20 fatty di-acid moiety that promotes albumin binding, enabling once-weekly dosing. Clinical trials consistently demonstrate it delivers the most substantial weight reduction among incretin-based therapies, with up to 22.5% mean body weight loss at 72 weeks.
17 vendors tracked by PeptideAtlas list Tirzepatide, priced from $20.00 to $320. The lowest price per milligram is $1.00/mg at Lipeptides (20mg). 101 independent Janoshik purity tests cover Tirzepatide across 51 vendors. Results range from 99.0% to 100.0%.
Category: Metabolic / Dual GIP-GLP-1 Agonist. Evidence rating: A (strong human clinical data).
Clinical status: FDA-approved (Mounjaro for T2D, Zepbound for obesity and OSA)
Tirzepatide (MW ~4813 g/mol, C225H348N48O68) simultaneously activates both GIP (glucose-dependent insulinotropic polypeptide) and GLP-1 (glucagon-like peptide-1) receptors. This dual agonism enhances glucose-dependent insulin secretion, suppresses glucagon, slows gastric emptying, increases…
Research base: 275 registered clinical trials and 239 indexed publications reference Tirzepatide.
Safety considerations: Common (5%+ in trials): abdominal pain, burping, constipation, diarrhea, dyspepsia, fatigue, GERD, hair loss, hypersensitivity reactions, injection site reactions, nausea, vomiting; Serious but rare: pancreatitis, gallbladder events, dehydration leading to kidney problems; FDA boxed warning for thyroid C-cell tumors (rodent data); call doctor for neck lump, swallowing difficulty, hoarseness, or shortness of breath.
Reviewed by the PeptideAtlas Editorial Team.
| Molecular weight | ~4813.5 g/mol |
|---|---|
| Half-life | ~5 days (116 hours) |
| Bioavailability | ~80% SC |
| Production method | synthetic |
| Anti-doping status | not-prohibited |
| US regulatory status | FDA-approved: Mounjaro (T2D, adults and children 10+) and Zepbound (obesity/overweight with comorbidities, severe OSA including new sleep apnea approval). Compounding fully prohibited for 503B facilities. Prescription only. |
| Vendor | Size | Price | Price per mg |
|---|---|---|---|
| Lipeptides | 20mg | $20.00 | $1.00/mg |
| All Peptides USA | 80MG | $130 | $1.63/mg |
| VPeptide | 65mg | $190 | $2.92/mg |
| Peptide Importer | 20mg | $68.00 | $3.40/mg |
| Growth Guys | 60mg | $225 | $3.75/mg |
| Great Northern Peptides | 40mg | $165 | $4.13/mg |
| The Peptide Labs | 20MG | $100 | $5.00/mg |
| Red Leaf Peptides | 20mg | $110 | $5.50/mg |
| Prime Lab Peptides | 30mg | $170 | $5.67/mg |
| Buy Peptides Australia | 50mg | $320 | $6.40/mg |
| Colorado Research Peptides | 10mg | $65.00 | $6.50/mg |
| Verasynlabs | 20MG | $140 | $7.00/mg |
| Lucky Link Peptides | 30MG | $249 | $8.30/mg |
| Sigma Peptides | 30MG | $300 | $10.00/mg |
| Purity Peptides | 10mg | $105 | $10.50/mg |
| Loti Labs | 10mg | $149 | $14.90/mg |
| Lab Trust Peptides | 10mg | $180 | $18.00/mg |
| Vendor | Best tested purity |
|---|---|
| Bad and Boujee/opaat | 100.0% |
| Zztai Peptide | 100.0% |
| Inno Peptides | 100.0% |
| Heman Peptide HM | 99.9% |
| Peptide Gurus | 99.9% |
| ZLZ Peptide | 99.9% |
| Hangzhou Mandy Biotechnology | 99.9% |
| niwza1120 | 99.9% |
| Hangzhou sigmabiotech | 99.9% |
| Qing Li Peptide | 99.9% |
| Yiwu Aozuo Trading Firm | 99.9% |
| Oasis Labs | 99.9% |
| SSR Bio | 99.9% |
| Henan Sahe Peptide | 99.9% |
| Reta-Peptide | 99.9% |
| lilipetide | 99.9% |
| Modern Peptides | 99.8% |
| uwa-biotech | 99.8% |
| Cocer Peptides | 99.8% |
| Eros Peptides | 99.8% |
| Qingdao Sigma Chemical QSC | 99.8% |
| [email protected] | 99.8% |
| [email protected] | 99.8% |
| [email protected] | 99.8% |
| [email protected] | 99.8% |
Independent lab tests: Tirzepatide purity test results.
The SURMOUNT-5 head-to-head trial (NCT05822830) showed 47% greater weight loss with tirzepatide compared to semaglutide over 72 weeks at maximum tolerated doses. Tirzepatide patients lost an average of 20.9% body weight vs 13.7% with semaglutide. However, individual responses vary and the choice depends on clinical context, insurance coverage, and side effect tolerance.
Switching should only be done under medical supervision. Dose titration protocols differ between the two medications.
Tirzepatide starts at 2.5 mg subcutaneously once weekly for 4 weeks, then increases to 5 mg. Further increases in 2.5 mg increments every 4+ weeks up to a maximum of 15 mg weekly. Available as single-dose pens in 2.5, 5, 7.5, 10, 12.5, and 15 mg strengths.
Appetite and craving changes begin in the first 4 weeks. Measurable weight loss occurs at 2-3 months, increasing over 6-12 months. In SURMOUNT-1, patients on 15 mg lost an average of 22.5% body weight over 72 weeks.
If within 4 days of the missed dose, take it as soon as remembered. If more than 4 days have passed, skip and continue the regular schedule. Do not inject two doses within 3 days of each other.
Vendors with independent lab tests for it: Growth Guys Canada, Reta-Peptide, MOB Peptides.
Vendors stocking it: VPeptide, Purity Peptides, Red Leaf Peptides, TMates, Loti Labs, Hangzhou Mandy Biotechnology, Zztai Peptide, ZePeptide, Wuhan Wansheng Biotechnology, Homopeptide, All Peptides USA, Sigma Peptides, NovaPeptide, Prime Lab Peptides, Colorado Research Peptides, Lab Trust Peptides, Verasynlabs, US Chem Labs, Discovery Research USA, Catalyst Peptides, Grewo Peptide, Peptides Lab UK, Lab Grade Peptides UK, Buy Peptides Australia, uwa-biotech, utherpeptide, Uther, Disguised Alpha, Growth Guys, Great Northern Peptides, The Peptide Labs, Toronto Peptides, Montreal Peptides, Advanced Peptides Australia, Lipeptides, Shandong Shengyuan Peptide Technology, Hunan GoodPeptides Biotech Co, Xianhong Tong XHT Peptides, Shenzhen Loga Tech LG LOGA, Hangzhou Youngpeptide Biotechnology HYB.
Coverage on this site: Seoul seizes 4,155 illegal Wegovy and Mounjaro imports in six months, PEC Purification for GLP-1 Manufacturing: Liraglutide Case Study, FDA's Compounded GLP-1 Warning Letters and the Embody Telehealth Model, Oral Wegovy Outruns Foundayo in the First Full Quarter of Oral Competition, GLP-1 therapy tied to rapid gains in mood and sleep in obesity, Meant launches LegitScript-certified GLP-1 telehealth platform.
Independent lab results for Tirzepatide: Tirzepatide 30MG — Independent Lab Test Results, Tirzepatide 20mg — Independent Lab Test Results, Tirzepatide 50 Mg — Independent Lab Test Results, Tirzepatide 60mg — Independent Lab Test Results, Tirzepatide 40mg — Independent Lab Test Results, Tirzepatide — Independent Lab Test Results.