Human RCT
Mensch
Rosenstock J. et al. 2021
Reduction in HbA1c versus placebo and versus semaglutide observed in randomised trials
What does NOT follow: Effect size varies by study dose and concomitant therapy.
Peptide entry · Metabolic
Tirzepatide
LY3298176 · Mounjaro · Zepbound
Highest evidence
Human RCT
Studies recorded
3· 3 in humans
Legal status · US
PrescriptionScientific context only. Not medical advice, not a recommendation to use.
At a glance
Synthetic peptide that simultaneously activates the GLP-1 and GIP receptor (dual agonist). Approved in the US and EU for type 2 diabetes (Mounjaro) and obesity (Zepbound).
Researched for
Glycaemic control in type 2 diabetesWeight reduction in obesityCardiovascular outcomesSteatotic liver disease
Official status
US: Prescription
FDA-approved as Mounjaro (type 2 diabetes, 2022) and Zepbound (chronic weight management, 2023). Prescription-only.
01
Mechanism of action
Tirzepatide is a 39-amino-acid peptide acting as a dual agonist at the GLP-1 (glucagon-like peptide-1) and GIP (glucose-dependent insulinotropic polypeptide) receptors. Activation of both incretin receptors via G-protein-coupled signalling raises insulin secretion in a glucose-dependent manner, lowers glucagon secretion and delays gastric emptying. Centrally, satiety perception is modulated. A fatty-acid side chain binds to serum albumin and extends the half-life to about five days.
02
Evidence at a glance
Reading note. The distribution shows on which evidence tier each observation sits. Strong colours mark stronger evidence — weaker tiers are deliberately visible, not hidden.
03
What the studies show
Human RCT
Mensch
Jastreboff AM. et al. 2022
Weight loss over 72 weeks in the obesity-without-diabetes study population
What does NOT follow: Long-term data beyond 2 years are limited; rebound after discontinuation has been observed.
Human trial
Mensch
Reduction in liver fat (MRI-PDFF) reported in patients with non-alcoholic steatohepatitis
What does NOT follow: Phase-2 data; histological endpoints pending.
Human RCT
Mensch
Rosenstock J. et al. 2021
Gastrointestinal adverse events (nausea, vomiting, diarrhoea) are the most commonly documented events in the registration trials
What does NOT follow: Frequency increases with dose; often transient during the titration phase.
05
Pharmacokinetics
Theoretical concentration curve at a half-life of 116 h. Pure pharmacokinetic model — not a dosing recommendation.
Open in PK tool →Start time: t₀ = 0.0d
Repeat interval: off (single dose)
06
Routes of administration in the literature
Which routes of administration the available studies describe — neutral reporting, not a usage guide.
Subcutaneous
In all SURPASS and SURMOUNT registration trials administered subcutaneously once weekly (abdomen, thigh or upper arm).
06b
Amounts reported in sources
Which amounts were reported in which source — ordered by context (approval, trial, animal model, secondary literature, community).
06c
Storage & stability
What prescribing information and stability literature report about storing the substance — descriptive, not a mixing or usage guide.
Reconstituted · storage
Unopened: 2–8 °C, protected from light; do not freeze.
Reconstituted · shelf life
Limited storage at room temperature (below 30 °C) is permitted per the label for the period stated in the label.
What the stability literature describes
- •Freezing damages the drug; the label describes frozen pens as no longer usable.
- •Keep protected from light.
07
Known adverse events from studies
Factual reporting of what studies observed. Not a safety statement for individual use.
Human RCT
Nausea
Most frequent adverse event in the SURPASS and SURMOUNT trials; mostly dose-dependent and pronounced in the titration phase. From aggregated trial data — not an individual prediction.
häufig in Titrationsphase
Human RCT
Pancreatitis (rare)
Class effect of GLP-1 RAs. FDA boxed warning concerns thyroid C-cell tumours — observed in rat studies, not confirmed in humans.
selten
07b
Interactions & combinations
Documented interactions and contraindications from studies, prescribing information and guidelines. Where no data exists, this is stated.
Reporting of risks, NOT a combination guide. The absence of an entry does not mean „safe to combine“ but „not sufficiently studied“.
CautionOral hormonal contraceptivesHuman trial
The label warns that oral contraceptives may be less effective after start and after each dose increase (delayed gastric emptying); the label advises a non-oral method or a barrier method for 4 weeks.
Context: Risk reporting from the label, not a combination guide.
CautionInsulin / sulfonylureasHuman RCT
Increased risk of hypoglycaemia when combined.
Context: Risk reporting from the label.
08
Risks & hygiene aspects in the literature
What regulatory and scientific literature reports on risks, sterility and identity in non-pharmaceutical sources — descriptive, not a hygiene guide.
Thyroid C-cell carcinoma (boxed warning)
The FDA label contains a boxed warning based on tumours in rat studies. Clinical relevance in humans is not confirmed. Personal or family history of medullary thyroid carcinoma or MEN2 is a contraindication.
09
Regulatory voices
Direct statements from official assessment documents — paraphrased with date and source link.
FDAU.S. Food and Drug Administration
2023-11-08Press release on Zepbound approval for chronic weight management, November 2023.
Obesity and overweight are serious conditions that can be associated with some of the leading causes of death.
10b
What online communities discuss
Recurring themes from Reddit, Quora and patient forums — synthetically summarised, sources linked. Not scientific evidence, but a signal of what users report. Deliberately separated from the study base.
Non-scientific sources. What users report in forums — synthetically summarised, paraphrased, with link to source. Not validated by studies.
Sorted by discussion frequency · 2 Themen
11
Legal status by country
12
Reconstitution calculator
Pure mg/mL maths — works like a calculator. Not a usage recommendation.
Peptides ship as a dry powder. Once dissolved in a liquid (reconstitution), this calculator answers a single question: how much substance is in one millilitre of solution afterwards?
- 1Enter the vial's substance amount (printed on the label).
- 2Enter how much solvent you add.
- 3Result = concentration in mg per mL.
Printed on the label
/
Liquid you add
=
2.50
mg / mL
5 mg in 2 mL gives 2.50 mg/mL — each millilitre contains 2.50 mg of substance.
14
Study register
Human RCTRandomised controlled trialn = 478
Rosenstock J. et al. · 2021
Tirzepatide versus placebo as monotherapy in type 2 diabetes (SURPASS-1)
Concrete results
HbA1c reduction (highest dose arm)
−2.07%
vs Placebo · 40 Wochen
Findings:Significant HbA1c reduction was reported in the treatment arm versus placebo.
Human RCTRandomised controlled trialn = 2539
Jastreboff AM. et al. · 2022
Tirzepatide once weekly for the treatment of obesity (SURMOUNT-1)
Concrete results
Mean weight reduction (highest dose arm)
−20.9%
vs Placebo · 72 Wochen
Findings:Substantial weight reduction versus placebo was reported in the treatment arm.
Human RCTRandomised controlled trialn = 1879
Frías JP. et al. · 2021
Tirzepatide versus semaglutide once weekly in patients with type 2 diabetes (SURPASS-2)
Concrete results
HbA1c difference
−0.45 percentage points
vs Semaglutid 1 mg · 40 Wochen
15
Sources & method
Reviewed by
editor-placeholder
Last reviewed
2026-05-22
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