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Library/For Weight Loss/Tirzepatide
FDA ApprovedGLP-1 / GIP+2 more★ Most Stacked

Tirzepatide

Dual GIP and GLP-1 receptor agonist. The biggest weight-loss number ever recorded in a phase 3 trial — about 22.5% body weight at 72 weeks on the top dose.

Updated 19 May 2026Read 10 minEvidence ●●●●●Citations 60
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Free — puts Tirzepatide on your decision board.

Status
FDA
Class
GLP-1 / GIP
Evidence
5/ 5●●●●●
FDA approval (obesity)
Nov 2023
Phase 3 weight loss
22.5%
SURMOUNT-1 enrollment
2,539
⚠ MTC Black Box
Read this if
  • you've heard about Tirzepatide on a podcast and want to know if it's the real deal
  • you're on Wegovy or Ozempic and considering switching
  • your friend lost 40 lbs in 6 months and you want to know what they took
  • your doctor mentioned Zepbound and you want a second read before you ask
  • you got offered a 'tirzepatide pen' or a 'tirz + B12/B6' compounded vial from a cash-pay clinic and want to know what's actually in it — Eli Lilly's June 2024 open letter warned that tirzepatide-with-B12 products tested showed an unknown tirzepatide-B12 reaction impurity (≤10% of total polypeptide in their samples); the B12/B6/glycine 'add' is also a known channel for diluting the active to stretch margin
Skip this if
  • you're looking for a recovery or longevity peptide — this isn't either
  • you've already done your homework and just need a vendor
  • you or a first-degree relative have medullary thyroid carcinoma (MTC) or Multiple Endocrine Neoplasia 2 (MEN-2) — this is the FDA black-box stop, and self-sourcing skips the prescriber gate that's supposed to catch it
  • you're not willing to add a barrier method to your oral contraceptive for 4 weeks after every dose bump — Mounjaro PI Section 7.3
The 4 ways you can buy Tirzepatide
Brand
✓
FDA-approved
$300–$1,100/mo (LillyDirect cash to retail list)
Real pharmacy product; LillyDirect single-dose vials drop cash to $299–$449.
Compounded 503A
⚠
Prescription
$179–$499/mo
Pharmacy-grade — but most large compounders were shut by Lilly's 2025 lawsuits.
RUO (research-only)
✓
Sold 'for research only'
$60–$200/mo
No purity guarantee — you reconstitute it yourself.
Gray market
✓
Unregulated overseas import
$10–$50/mo
Crypto/Wise pay, no published COA; cheaper per mg than RUO at larger box sizes.
Click any lane for the full Sourcing breakdown.
First 90 days · Tirzepatide
Weeks 1–2
GI side effects start. Nausea is the rate-limiter. Don't titrate up if you can't tolerate the starting dose — the side-effect curve gets steeper, not flatter.
Weeks 4–8
Appetite suppression becomes the obvious effect. 1–2 lbs/week is typical. Hit a plateau? Hold the dose, don't immediately bump.
Week 12 — decide
Bloodwork: A1c, lipids, liver enzymes, fasting insulin. Visible weight change should be 5–10%. If the trajectory is flat at 12 weeks and you've titrated, this isn't your molecule.
Quit if
  • Pancreatitis-like pain (severe upper-abdominal, won't sit still): stop and call your doctor.
  • Gallbladder pain or persistent vomiting that won't resolve.
  • Severe muscle loss without resistance training (the 'GLP-1 face' is real — protein floor matters).
  • 12 weeks at full dose with zero weight movement (rare, but real).
Identity

What it is.

Tirzepatide is a synthetic that activates two gut-hormone receptors at once: GLP-1 and GIP. Most weight-loss peptides hit only . Tirzepatide hits both, which is why it tends to outperform them in head-to-head trials.

It was developed by Eli Lilly and approved by the FDA in 2022 for type 2 diabetes (sold as Mounjaro) and in 2023 for chronic weight management (sold as Zepbound). It is given as a once-weekly injection. The active molecule is identical in both products — only the label and the marketing differ.

Mechanically, the arm slows gastric emptying and blunts appetite. The GIP arm appears to amplify that effect and may improve how the body handles fat in adipose tissue. The combined receptor pull is the reason it sits at the top of the weight-loss league table right now.

TL;DR

TL;DR. 30-second version.

  1. 01
    What it is.
    A weekly injection that hits two gut hormone receptors instead of one. GIP plus GLP-1.
  2. 02
    What we know in humans.
    SURMOUNT-1 (n=2,539): mean weight loss of 22.5% at the 15 mg dose over 72 weeks. SURPASS trials show large A1c drops in type 2 diabetes.
  3. 03
    Where the compounded supply went.
    The FDA shortage closed in October 2024 and Lilly's 2025 lawsuits (Mochi, Henry, Hims, Hers, Strive, Empower, Fella, Willow) shut most large 503A pharmacies. The two real lanes left are brand (LillyDirect cash $299–$449) or RUO. The cash-pay middle has mostly collapsed.
  4. 04
    What to know first.
    Side effects are mostly GI: nausea, diarrhea, constipation. Black-box warning for medullary thyroid carcinoma based on rat data. Oral contraceptives may fail — Mounjaro PI Section 7.3 says switch to non-oral or add a barrier method for 4 weeks after each dose escalation.
  5. 05
    What we'd do.
    Yes if BMI is 30+ (or 27+ with a metabolic comorbidity) and you've honestly tried sleep, protein, walking, and lifting first — tirzepatide is the most effective tool we have for that range, full stop. Skip it if you're chasing the last 10 lbs of vanity weight or planning to stop at six months and hope the result holds (it won't). Plan the off-ramp from day one and eat 1.6 g/kg protein while you lift, or you'll end up smaller and weaker.
Mechanism

Mechanism.

Tirzepatide is a dual agonist at the GLP-1 receptor and the GIP receptor, both Gs-coupled receptors expressed in pancreatic beta cells, the gut, the brain (especially the hypothalamus and area postrema), and adipose tissue. Affinity is roughly equivalent to native GIP at GIP-R and somewhat reduced versus native at GLP-1R — the molecule is biased, not balanced, and the GIP arm is the part the older single-agonists don't have.

The terminal is approximately 5 days. That's the number that drives once-weekly dosing. Plasma steady state is reached at around four weeks. The molecule is engineered with a C20 fatty diacid chain that binds albumin, which is what produces the long half-life — it's the same trick semaglutide uses, executed differently.

Onset of receptor engagement is essentially immediate after injection (peak plasma concentration around 24–72 hours). Onset of *effect the human notices* is slower: appetite suppression typically shows up within the first week, GI side effects within the first few days, and meaningful weight movement at 4–8 weeks. The drug is still working at week 72 in SURMOUNT-1; the curve hadn't plateaued.

Downstream of receptor binding, several things happen at once. In pancreatic beta cells, both receptors potentiate glucose-dependent insulin secretion via cAMP and PKA — meaning insulin is released only when glucose is elevated, which is why hypoglycemia risk is low as a monotherapy. In the brain, GLP-1R activation in the arcuate nucleus and brainstem suppresses appetite and slows gastric emptying through vagal pathways. In adipose tissue, GIP-R activation appears to improve insulin sensitivity and may promote fat over visceral, though the human-tissue mechanism here is still being argued out. Glucagon secretion is suppressed glucose-dependently. There is no direct effect on resting energy expenditure of any meaningful size — the weight loss is driven by reduced caloric intake, full stop.

What this means for the human: nausea and early satiety within the first 72 hours, often worsening at each dose escalation. Appetite — specifically the *food noise* people describe — drops within 1–2 weeks. HbA1c starts moving at 4 weeks and lands roughly 1.5–2.0 points lower by week 24 in diabetic populations. Weight loss accelerates around week 8–12 and continues for the duration of dosing. Lean mass drops alongside fat mass unless protein intake and resistance training are non-negotiable — about a third of the loss is lean tissue otherwise.

CYP / transporter interactions are minimal. Tirzepatide is a ; it's not metabolized by the cytochrome system and has no clinically significant CYP induction or inhibition. The one real interaction is gastric: by slowing gastric emptying, it can change the absorption kinetics of orally dosed drugs taken with it — most relevantly, oral contraceptives (Lilly recommends a backup method or a switch to non-oral contraception for four weeks after starting and after each dose escalation). Insulin and sulfonylureas need to be down-titrated by the prescriber; otherwise hypoglycemia is the predictable result.

Evidence

Evidence. What we actually know in humans.

Unusually for the peptides we cover, the human evidence here is real and large. The SURMOUNT-1 trial randomized 2,539 adults with obesity to tirzepatide or placebo for 72 weeks. The 15 mg dose group lost an average of 22.5% of body weight. SURMOUNT-2 replicated the effect in people with type 2 diabetes. SURMOUNT-3 and -4 looked at maintenance.

This is the highest weight-loss number ever produced by a non-surgical intervention in a . It is also durable while the drug is taken, and largely lost when it is stopped — which is the part nobody likes hearing.

The headline numbers below come from the published SURMOUNT data and Lilly's prescribing label, not from clinic marketing.

Human-Evidence Factbox
FDA approval (obesity)
Nov 2023
Phase 3 weight loss
22.5%
SURMOUNT-1 enrollment
2,539
Dosing
Weekly subQ
List price (Zepbound)
~$1,069/mo · LillyDirect cash $299–$449
503A compounded supply
Mostly shut (Lilly 2025 lawsuits)
Tirz + B12 reaction impurity
≤10% of polypeptide in Lilly's 2024 testing
Tirz + B12/B6 vial
Dilution tell — additives mask under-dose
Oral contraceptive interaction
Use barrier or non-oral × 4 wk post-escalation
Protein floor (lean-mass sparing)
1.6 g/kg/d
Discontinuation rate (AE)
~6%
"Tirzepatide produced the largest reductions in body weight ever observed in a phase 3 obesity trial.
— Jastreboff et al., NEJM 2022
Dose

Dose. The actual protocol.

Route
Subcutaneous (SC)
Weight loss (Zepbound) and T2D (Mounjaro).
Once-weekly. 20-wk ladder to 15mg/wk. 22.5% weight loss at top dose in SURMOUNT-1. Abdomen / thigh / upper arm rotation.
FDA
Human trialFDA approvedVerified 2026-05-04
Start dose
2.5mg/wk
Target dose
15mg/wk
Titration ladder
20-wk ladder: 2.5 → 5 → 7.5 → 10 → 12.5 → 15 mg/wk
The honest read

15mg/wk is the TOP / target dose, not the starting dose. Most people never reach it due to GI side effects. 22.5% weight loss at top dose.

Source
SURMOUNT-1 (Jastreboff 2022)PMID 35658024
Reconstitute from a vial? We do the math.
Open the calculator →
Sourcing

Sourcing. Where the cohort actually buys.

By source — cost, legality, risk
  • Brand — Mounjaro / Zepbound
    $300–$1,100/mo (LillyDirect cash to retail list)
    FDA-approved · prescription
    Lowest. Real pharmacy product; LillyDirect single-dose vials drop cash to $299–$449.
  • Compounded 503A pharmacy
    $179–$499/mo
    Prescription · supply collapsing post-shortage
    Mid. Pharmacy-grade — but most large compounders were shut by Lilly's 2025 lawsuits.
  • RUO research peptide
    $60–$200/mo
    Sold 'for research only'
    Highest. No purity guarantee — you reconstitute it yourself.
  • Gray-market raw
    $10–$50/mo
    Unregulated overseas import
    Crypto/Wise pay, no published COA; cheaper per mg than RUO at larger box sizes.
Annotated COA · Tirzepatide
Sample row layout. A clean Certificate of Analysis for Tirzepatide should show the green-flag rows below; the burnt rows are the recurring tells that mean stop.
  • Peptide identity
    Tirzepatide (4813.5 Da, 39-mer with C20 fatty acid)
    Pass
  • Identity method
    Mass spec (MS), MW within ±0.1%
    Pass
  • Purity (HPLC)
    ≥98%
    Pass
  • Endotoxin (LAL)
    <5 EU/mg
    Pass
  • Sterility / bioburden
    Tested, pass — required for injectable
    Pass
  • B12 / B6 / glycine 'add-in'
    Polypeptide reaction impurity ≤10% (Lilly 2024)
    Red flag
  • 'Tirz + B12' combo vial
    Dilution channel — masks under-dose
    Red flag
  • Identity by IR only
    Cannot distinguish tirz from mixed-product
    Red flag
  • Lot # on vial vs COA
    Must match exactly
    Pass
  • Brand pen vs vial
    FDA pen has its own QC; only RUO vials need COA reading
    Context
Most common mismatch
Vial labeled 'tirzepatide + B12' or 'tirzepatide blend.' Lilly's June 2024 open letter documented an unknown tirz-B12 polypeptide reaction impurity at ≤10% of total polypeptide in tested samples; the B12 add is also a known dilution channel. The cleanest COA shows tirzepatide alone, mass-spec confirmed, no co-formulation.
If you go RUO or grey, demand these tests

Brand pharmacy product comes with FDA-mandated QC. 503A compounded comes with USP-compliant pharmacy QC. RUO and grey-market vials come with whatever the vendor decides to publish — which is why the buyer needs to know what to ask for.

  • Identity (mass spec). Confirms the molecule on the label is what’s in the vial. Target MW must match.
  • Purity (HPLC). Target ≥98%. Below 95% is a red flag.
  • Endotoxin (LAL). Target <5 EU/mg. The most-skipped test on shady COAs.
  • Sterility / bacterial contamination. Required for anything injectable.
  • Dose accuracy. Stated mg/vial within ±5% of measured.
COA reading checklist
  • · Identity by mass spec (MS), molecular weight matches label
  • · Purity by HPLC, ≥98%
  • · Endotoxin tested (LAL), <5 EU/mg
  • · Sterility / bacterial contamination tested
  • · Dated within the last 90 days
  • · Lot/batch number matches the vial in your hand
  • · Lab name is third-party (not the vendor) and has a real web presence
Red-flag patterns
  • ✕ COA missing endotoxin (the #1 skipped test)
  • ✕ COA dated >12 months ago
  • ✕ Lot # different from the vial
  • ✕ Identity by IR-only, not MS
  • ✕ Disclaimer text obviously cut-and-pasted from another vendor
  • ✕ Lab name with no web presence
Lane availability
All four lanes exist. Brand (Mounjaro, Zepbound) is the Lilly product, prescription-only, paid through insurance or cash at retail pharmacy. 503A was the cash-pay backbone for two years during the FDA shortage and is now collapsing — the shortage was declared resolved in October 2024, and Lilly's 2025 lawsuits against Mochi, Henry Meds, Hims, Hers, Strive, Empower, Fella, and Willow have shut most large-volume compounded supply. Some 503A pharmacies still ship under "personalization" exceptions; most have pivoted to retatrutide. ("research ") supply is huge and untouched by the litigation. Gray-market overseas raws exist but the active compounders cleared most of that channel by underpricing it.
Where this cohort actually sources
The on-label cohort goes through telehealth or a primary-care prescription. The off-label cosmetic-weight-loss crowd was on Mochi, Henry Meds, Hims, Hers, Strive, Empower, Fella, and Willow during the shortage; many have transitioned to since the lawsuits. r/tirzepatidecompound and adjacent subs are where supply intel circulates.
Peptide-specific red flags
Pre-mixed "ready-to-inject" multi-dose pens from gray vendors are routinely under-dosed — independent testing has found 30–60% of label claim. vials labeled with "B12" or "B6" combinations are the legacy of a 2024 503A workaround and have no clinical rationale. vials marketed as "10mg" but reconstituted to a concentration that doesn't math out are a recurring identity-vs-dose mismatch.
Legal frame
Brand and 503A both require a real prescription from a licensed prescriber. is sold "for research use only" and personal injection is technically off-label for the buyer; possession is not currently prosecuted. Gray import is a customs risk.
This compound is available across all four sourcing tiers. For the end-to-end picture — how peptide raws move from API factory → wholesale broker → 503A pharmacy / RUO vendor / your door — read How peptides actually get to your door →
Safety

Safety. Side effects.

The big one is GI: nausea, constipation, diarrhea, and reflux, especially in the first weeks and at every dose escalation. Most people titrate through it. Some don't, and stop the drug.

Less common but documented: gallbladder issues, pancreatitis, injection-site reactions, and the cosmetic complaint people call "Ozempic face" — fat loss in the cheeks that ages you on camera. Lean-mass loss without resistance training is the side effect most people underweight.

The Tirzepatide label carries a black-box warning for medullary thyroid carcinoma (MTC) based on a rat study showing thyroid C-cell tumors at high doses. The signal has not been replicated in humans on tirzepatide or its older cousin liraglutide despite hundreds of thousands of patient-years of post-marketing data.

What we actually know: /GIP receptors are present on rodent thyroid C-cells in much higher density than in humans, which is the leading explanation for why rats grew tumors and humans seem not to. The official contraindication remains: personal or family history of MTC, or Multiple Endocrine Neoplasia type 2 (MEN2) = absolute no.

Nobody knows
what 30 or 50 years of weekly tirzepatide does to the human thyroid. The post-marketing surveillance is good but the time horizon is short. If you have a thyroid history, talk to an endocrinologist — not us, not TikTok.
Editorial Position

Editorial position.

Here's how we'd think about it if it were us.

Use case where it makes sense:
a BMI in the 30+ range, or 27+ with a metabolic comorbidity, after honest attempts at the basics (sleep, protein, walking, lifting). Tirzepatide is the most effective tool we have for this range, full stop.
Use case where it doesn't:
trying to lose the last 10 lbs of vanity weight, or using it as a cosmetic shortcut around lifestyle change you haven't actually tried. The muscle-loss problem is real — about a third of the weight lost on these drugs is lean mass unless you eat enough protein and lift heavy things. People who skip that part end up smaller and weaker, then rebound when they stop.

If you do start it, plan the off-ramp from day one. Most weight returns within a year of stopping cold.

Stack-fit · how it pairs
Combines well with:
  • Cagrilintide — amylin agonist, additive satiety + slows gastric emptying. Best-evidenced partner. CagriSema phase 3 hit ~22.7% at 68 weeks.
  • Resistance training program — not a , but stacking with serious lifting is the single biggest determinant of whether the weight loss is fat or lean mass.
  • Protein floor (1.6g/kg minimum) — appetite suppression makes protein collapse without an explicit target.
Avoid stacking with:
  • Other GLP-1 agonists (semaglutide, liraglutide, retatrutide, mazdutide, survodutide, orforglipron). Receptor saturation, additive nausea, no additive benefit. Pick one.
  • Sermorelin / CJC-1295 / ipamorelin — GH-secretagogue cohort that elevates . Layering over chronic caloric deficit complicates the body-comp picture and the cancer-risk math.
Sequencing:
Tirzepatide is the spine of the — start it first, titrate to a stable dose, then layer additions. Don't add anything in the first 8 weeks while you're still finding the GI ceiling.
Citations

Citations.

  1. 01Aronne LJ, et al. Continued Treatment With Tirzepatide for Maintenance of Weight Reduction in Adults With Obesity: The SURMOUNT-4 Randomized Clinical Trial. JAMA. 2024;331(1):38-48. PMID: 38078870.
  2. 02Frías JP, et al. Tirzepatide versus Semaglutide Once Weekly in Patients with Type 2 Diabetes. The New England journal of medicine. 2021;385(6):503-515. PMID: 34170647.
  3. 03Jastreboff AM, et al. Tirzepatide for Obesity Treatment and Diabetes Prevention. The New England journal of medicine. 2025;392(10):958-971. PMID: 39536238.
  4. 04Garvey WT, et al. Tirzepatide once weekly for the treatment of obesity in people with type 2 diabetes (SURMOUNT-2): a double-blind, randomised, multicentre, placebo-controlled, phase 3 trial. Lancet (London, England). 2023;402(10402):613-626. PMID: 37385275.
  5. 05Zhao L, et al. Tirzepatide for Weight Reduction in Chinese Adults With Obesity: The SURMOUNT-CN Randomized Clinical Trial. JAMA. 2024;332(7):551-560. PMID: 38819983.
+Show all 60 citations
  1. 06France NL, et al. Tirzepatide: A Review in Type 2 Diabetes. Drugs. 2024;84(2):227-238. PMID: 38388874.
  2. 07Dahl D, et al. Effect of Subcutaneous Tirzepatide vs Placebo Added to Titrated Insulin Glargine on Glycemic Control in Patients With Type 2 Diabetes: The SURPASS-5 Randomized Clinical Trial. JAMA. 2022;327(6):534-545. PMID: 35133415.
  3. 08Nicholls SJ, et al. Comparison of tirzepatide and dulaglutide on major adverse cardiovascular events in participants with type 2 diabetes and atherosclerotic cardiovascular disease: SURPASS-CVOT design and baseline characteristics. American heart journal. 2024;267:1-11. PMID: 37758044.
  4. 09Malhotra A, et al. Tirzepatide for the Treatment of Obstructive Sleep Apnea and Obesity. The New England journal of medicine. 2024;391(13):1193-1205. PMID: 38912654.
  5. 10Nauck MA, et al. Tirzepatide, a dual GIP/GLP-1 receptor co-agonist for the treatment of type 2 diabetes with unmatched effectiveness regrading glycaemic control and body weight reduction. Cardiovascular diabetology. 2022;21(1):169. PMID: 36050763.
  6. 11Packer M, et al. Tirzepatide for Heart Failure with Preserved Ejection Fraction and Obesity. The New England journal of medicine. 2025;392(5):427-437. PMID: 39555826.
  7. 12Rodriguez PJ, et al. Semaglutide vs Tirzepatide for Weight Loss in Adults With Overweight or Obesity. JAMA internal medicine. 2024;184(9):1056-1064. PMID: 38976257.
  8. 13Rosenstock J, et al. Efficacy and safety of a novel dual GIP and GLP-1 receptor agonist tirzepatide in patients with type 2 diabetes (SURPASS-1): a double-blind, randomised, phase 3 trial. Lancet (London, England). 2021;398(10295):143-155. PMID: 34186022.
  9. 14Loomba R, et al. Tirzepatide for Metabolic Dysfunction-Associated Steatohepatitis with Liver Fibrosis. The New England journal of medicine. 2024;391(4):299-310. PMID: 38856224.
  10. 15Sattar N, et al. Tirzepatide cardiovascular event risk assessment: a pre-specified meta-analysis. Nature medicine. 2022;28(3):591-598. PMID: 35210595.
  11. 16Karagiannis T, et al. Subcutaneously administered tirzepatide vs semaglutide for adults with type 2 diabetes: a systematic review and network meta-analysis of randomised controlled trials. Diabetologia. 2024;67(7):1206-1222. PMID: 38613667.
  12. 17Heise T, et al. Tirzepatide Reduces Appetite, Energy Intake, and Fat Mass in People With Type 2 Diabetes. Diabetes care. 2023;46(5):998-1004. PMID: 36857477.
  13. 18Gettman L. New Drug: Tirzepatide (Mounjaro(™)). The Senior care pharmacist. 2023;38(2):50-62. PMID: 36751934.
  14. 19Willard FS, et al. Tirzepatide is an imbalanced and biased dual GIP and GLP-1 receptor agonist. JCI insight. 2020;5(17). PMID: 32730231.
  15. 20Rosenstock J, et al. Tirzepatide vs Insulin Lispro Added to Basal Insulin in Type 2 Diabetes: The SURPASS-6 Randomized Clinical Trial. JAMA. 2023;330(17):1631-1640. PMID: 37786396.
  16. 21Skelley JW, et al. The impact of tirzepatide and glucagon-like peptide 1 receptor agonists on oral hormonal contraception. Journal of the American Pharmacists Association : JAPhA. 2024;64(1):204-211.e4. PMID: 37940101.
  17. 22Del Prato S, et al. Tirzepatide versus insulin glargine in type 2 diabetes and increased cardiovascular risk (SURPASS-4): a randomised, open-label, parallel-group, multicentre, phase 3 trial. Lancet (London, England). 2021;398(10313):1811-1824. PMID: 34672967.
  18. 23Look M, et al. Body composition changes during weight reduction with tirzepatide in the SURMOUNT-1 study of adults with obesity or overweight. Diabetes, obesity & metabolism. 2025;27(5):2720-2729. PMID: 39996356.
  19. 24Aronne LJ, et al. Tirzepatide as Compared with Semaglutide for the Treatment of Obesity. The New England journal of medicine. 2025;393(1):26-36. PMID: 40353578.
  20. 25Ravussin E, et al. Tirzepatide did not impact metabolic adaptation in people with obesity, but increased fat oxidation. Cell metabolism. 2025;37(5):1060-1074.e4. PMID: 40203836.
  21. 26Karagiannis T, et al. Management of type 2 diabetes with the dual GIP/GLP-1 receptor agonist tirzepatide: a systematic review and meta-analysis. Diabetologia. 2022;65(8):1251-1261. PMID: 35579691.
  22. 27Gastaldelli A, et al. Effect of tirzepatide versus insulin degludec on liver fat content and abdominal adipose tissue in people with type 2 diabetes (SURPASS-3 MRI): a substudy of the randomised, open-label, parallel-group, phase 3 SURPASS-3 trial. The lancet. Diabetes & endocrinology. 2022;10(6):393-406. PMID: 35468325.
  23. 28Heerspink HJL, et al. Effects of tirzepatide versus insulin glargine on kidney outcomes in type 2 diabetes in the SURPASS-4 trial: post-hoc analysis of an open-label, randomised, phase 3 trial. The lancet. Diabetes & endocrinology. 2022;10(11):774-785. PMID: 36152639.
  24. 29Sumithran P, et al. Cardiovascular effects of tirzepatide. The Journal of endocrinology. 2025;264(2). PMID: 39751188.
  25. 30Tan B, et al. Efficacy and safety of tirzepatide for treatment of overweight or obesity. A systematic review and meta-analysis. International journal of obesity (2005). 2023;47(8):677-685. PMID: 37253796.
  26. 31Zeng Q, et al. Safety issues of tirzepatide (pancreatitis and gallbladder or biliary disease) in type 2 diabetes and obesity: a systematic review and meta-analysis. Frontiers in endocrinology. 2023;14:1214334. PMID: 37908750.
  27. 32Samms RJ, et al. GIPR agonism mediates weight-independent insulin sensitization by tirzepatide in obese mice. The Journal of clinical investigation. 2021;131(12). PMID: 34003802.
  28. 33Inagaki N, et al. Efficacy and safety of tirzepatide monotherapy compared with dulaglutide in Japanese patients with type 2 diabetes (SURPASS J-mono): a double-blind, multicentre, randomised, phase 3 trial. The lancet. Diabetes & endocrinology. 2022;10(9):623-633. PMID: 35914543.
  29. 34Cai W, et al. Tirzepatide as a novel effective and safe strategy for treating obesity: a systematic review and meta-analysis of randomized controlled trials. Frontiers in public health. 2024;12:1277113. PMID: 38356942.
  30. 35Krüger N, et al. Semaglutide and Tirzepatide in Patients With Heart Failure With Preserved Ejection Fraction. JAMA. 2025;334(14):1255-1266. PMID: 40886075.
  31. 36Masson W, et al. Anti-inflammatory effects of tirzepatide: a systematic review and meta-analysis. Reviews in endocrine & metabolic disorders. 2026;27(1):5-15. PMID: 41032183.
  32. 37Syed YY. Tirzepatide: First Approval. Drugs. 2022;82(11):1213-1220. PMID: 35830001.
  33. 38Regmi A, et al. Tirzepatide modulates the regulation of adipocyte nutrient metabolism through long-acting activation of the GIP receptor. Cell metabolism. 2024;36(7):1534-1549.e7. PMID: 38878772.
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