GLP-1, GIP, and glucagon receptor agonist
Not FDA approved; investigational as of October 2026.
Study: Human trials found substantial weight loss in adults with obesity without diabetes.15
Community: Community reports focus on reduced appetite and weight management. Research vials are not the trial formulation.8
Early human development includes glucose-control studies.4
39 residues · N → C29
Y–Aib–Q–G–T–F–T–S–D–Y–S–I–αMeL–L–D–K–K*–A–Q–Aib–A–F–I–E–Y–L–L–E–G–G–P–S–S–G–A–P–P–P–SAib at 2 and 20; αMeL = alpha-methylleucine at 13; K* at 17 carries the lipidated side chain. C-terminal amide. Backbone positions include the modifications described in the systematic identity.
Formula excludes counterions. The catalog lists a sodium salt with variable sodium content; this is not a retail-vial identity test.
Illustrative model using reported human data.
Five half-lives in this simplified model. This is not a prediction of when effects stop.
Reported human estimate; albumin binding prolongs exposure. An idealized elimination curve does not model absorption, accumulation or individual response.
Population: Adults with type 2 diabetes in a phase 1b trial
100 × 2−time / half-life. Time zero is a reference level, not the moment of administration. Absorption, repeated dosing, metabolites and clinical effects are not modeled. Five half-lives leaves 3.125%, not zero. This curve cannot determine a dosing interval.
This value is reported by a secondary reference. The stated attribution has not been independently verified as a route- and formulation-matched human PK measurement.
Illustrative scenario using an unverified reference estimate.
Five half-lives in this estimated model. This is not a prediction of when effects stop.
Population: Not established by the reference estimate
Source’s stated attribution: Phase 2 Clinical Trial Data (Eli Lilly)
Source’s reported peak time: 1 day. This has not been independently confirmed and is not used in the elimination curve.
100 × 2−time / half-life. Time zero is a reference level, not the moment of administration. Absorption, repeated dosing, metabolites and clinical effects are not modeled. Five half-lives leaves 3.125%, not zero. This curve cannot determine a dosing interval.
TRIUMPH-1 reported mean changes of −17.6%, −23.7% and −25.0% for 4, 9 and 12 mg versus −3.9% for placebo (treatment-regimen estimand).5
Appetite 1–4 weeks, continuing change over months; its staged percentage-loss predictions are not personal forecasts.31
Trial outcomes at 80 weeks; interpretation depends on estimand/population.31
These are reported timelines, not a prediction of your response.
Scroll to compare all columns →
| Route | Dose | Frequency | Goal / evidence | Duration | References |
|---|---|---|---|---|---|
| SubQSubcutaneous | 4 mgMaintenance | Once weekly | Weight reduction (TRIUMPH-1)2,339 adults with obesity without diabetesHuman study | 80 weeks | 5 |
Population 2,339 adults with obesity without diabetes Context Randomized maintenance targets after trial escalation, not starting-dose instructions. Source dose wording 4, 9 or 12 mg maintenance | |||||
| SubQSubcutaneous | 9 mgMaintenance | Once weekly | Weight reduction (TRIUMPH-1)2,339 adults with obesity without diabetesHuman study | 80 weeks | 5 |
Population 2,339 adults with obesity without diabetes Context Randomized maintenance targets after trial escalation, not starting-dose instructions. Source dose wording 4, 9 or 12 mg maintenance | |||||
| SubQSubcutaneous | 12 mgMaintenance | Once weekly | Weight reduction (TRIUMPH-1)2,339 adults with obesity without diabetesHuman study | 80 weeks | 5 |
Population 2,339 adults with obesity without diabetes Context Randomized maintenance targets after trial escalation, not starting-dose instructions. Source dose wording 4, 9 or 12 mg maintenance | |||||
| SubQ | 2 mgStarting dose | Weekly x 4 weeks, then increase | Phase 3 start (TRIUMPH)Reference report | Continuous therapy - effects reverse upon discontinuation | 31 |
Population Population not independently verified; see the reference and linked research. Context Reported in Pep-Pedia’s educational protocol table. Study attribution and applicability to this exact product are not independently established. No established one-hour contraceptive rule or safe research-product combination. Source tabs Injectable | |||||
| SubQ | 4, 9, or 12 mg | Once weekly | Phase 3 targets (TRIUMPH)Reference report | Continuous therapy - effects reverse upon discontinuation | 31 |
Population Population not independently verified; see the reference and linked research. Context Reported in Pep-Pedia’s educational protocol table. Study attribution and applicability to this exact product are not independently established. No established one-hour contraceptive rule or safe research-product combination. Source tabs Injectable | |||||
| SubQ | 0.5-1 mgStarting dose | Once weekly | Community start (not in trials)Reference report | Continuous therapy - effects reverse upon discontinuation | 31 |
Population Population not independently verified; see the reference and linked research. Context Reported in Pep-Pedia’s educational protocol table. Study attribution and applicability to this exact product are not independently established. No established one-hour contraceptive rule or safe research-product combination. Source tabs Injectable | |||||
No protocols match these filters.
Study and label doses retain their study context. Reference reports are unvalidated practices, not personal treatment instructions. Ranges remain ranges; escalation stages are labeled.
Reported use periods and breaks. These do not establish a safe cycle or prove that breaks prevent tolerance.
Any time of day, maintain same day each week for consistency
Gastrointestinal events were the most common adverse events in TRIUMPH-1.
5Dose-related heart-rate increases occurred in phase 2.
1FDA identifies retatrutide as unapproved; trial findings do not validate online research products.
3GI symptoms, altered skin sensations and heart-rate increases.
Severe abdominal/RUQ pain, repeated vomiting/diarrhea, dehydration, hypoglycemia or excessive weight loss.
MTC/MEN2 risk and pregnancy require assessment; community starts differ from trial titration.
Not a complete safety screen. Discuss health decisions with a qualified clinician.
Check cautions and reported pairings. A compatibility claim does not establish that a combination is safe.
Incretin overlap.31
Reference report · Pep-Pedia label: Avoid CombinationGLP-1 overlap.31
Reference report · Pep-Pedia label: Avoid CombinationGI burden; combination unestablished.31
Reference report · Pep-Pedia label: Use CautionHypoglycemia risk.31
Reference report · Pep-Pedia label: Monitor CombinationSource timing rule unverified.31
Reference report · Pep-Pedia label: Requires TimingINR may change.31
Reference report · Pep-Pedia label: Monitor CombinationBackground trial therapy.31
Reference report · Pep-Pedia label: CompatibleBackground trial therapy.31
Reference report · Pep-Pedia label: CompatibleUntested; no proven GI protection.31
Reference report · Pep-Pedia label: CompatibleUntested pairing.31
Reference report · Pep-Pedia label: CompatibleThe cited obesity trial does not establish safety of self-directed combinations with semaglutide, tirzepatide or insulin.5
Research contextNo matching interactions. Try another name or filter.
Enter your peptide amount and container size. Get a volume and a simple measurement scale.
For dry powder, assuming negligible volume displacement. Use bacteriostatic water only if the formulation specifies it.
Amounts below are total blend mass. Ingredient amounts are listed separately.
| Pen units | Amount | Volume |
|---|
Enter an amount to calculate its volume and device setting.
The suggestion favors a simple 1, 2, or 5 × power-of-ten amount per unit, then the largest final volume that fits. It does not choose a dose or a biologically suitable concentration.
The water estimate applies only to dry powder and assumes negligible powder displacement. Final solution volume, specified diluent, solubility, stability, sterility, cartridge compatibility, and working fill limits must be established separately. No allowance is made for priming or transfer losses.
V2 measurement specification ↗Bacteriostatic water: formulation instructions ↗No FDA-approved retatrutide formulation or universal reconstitution instruction exists.3
A concentration calculation cannot establish a product's identity, sterility, stability or suitability for injection.3
Reported handling information, not a validated formulation or instruction to prepare an injectable product.
Pep-Pedia describes a research-powder preparation using bacteriostatic water.
The source describes gentle mixing and avoiding vigorous shaking.
The saline warning and 28-day interval are secondary-source claims, not a validated stability specification for every research vial.
Appearance and a purity certificate cannot establish sterility, identity, or suitability for injection.
Each amount below appears in at least two of four catalogs checked on October 12, 2026. This is a sample of recurring listings, not a ranking of the most popular sizes.
Labels describe nominal contents, not a dose or supplier endorsement. Approved and research products are not interchangeable.
Pep-Pedia reports these handling limits after mixing. They are not validated stability or sterility limits for your vial.
Lyophilized powder at room temperature; reconstituted solution refrigerated
Storage depends on the formulation, diluent, container, and handling. Follow the specific product label or pharmacist’s instructions.
Device units measure volume. Concentration determines the amount in mg.
Documented 1-unit V2 models
Use the numbered dose window. Whole-unit settings only; confirm the specification for your exact model.
100 units = 1 mL
Read the printed unit scale. A small line may represent 0.5, 1, or 2 units depending on the syringe.
mL syringes and calibrated pipettes
Drops, sprays and other pen clicks need their own verified volume per increment. They have no universal conversion.
3 mL is cartridge capacity. It does not mean you must prepare or load 3 mL. The original vial and the pen cartridge are different containers. This reference compares measurement scales; it does not establish product or route compatibility.
Long-term clinical outcomes and risks are still being studied.1
6 distinct primary sources or abstracts checked. Evidence may concern a parent compound, individual blend ingredient, animal, or cell model; it does not necessarily establish a benefit for this exact product.
Evidence definitions →No established one-hour contraceptive rule or safe research-product combination.
An investigational GLP-1, GIP and glucagon receptor agonist studied for obesity and metabolic disease. Human trials show substantial weight loss, but trial material and online research vials are not interchangeable.
Other names: Reta · LY3437943 · GLP-3
Not FDA approved; investigational as of October 2026.
Lipidated GIP/GLP-1/glucagon receptor agonist.106
39 amino acids · 4,731.33 Da
His-Aib-Glu-Gly-Thr-Phe-Thr-Ser-Asp-Val-Ser-Ser-Tyr-Leu-Glu-Gly-Gln-Ala-Ala-Lys-Glu-Phe-Ile-Ala-Trp-Leu-Val-Arg-Gly-Arg-Gly-Pro-Ser-Ser-Gly-Ala-Pro-Pro-Pro-SerReference description; checked chemical identity takes precedence when available.31
Activates GIP, GLP-1 and glucagon receptors affecting appetite, glucose regulation and energy expenditure.31
In 338 adults with obesity or overweight without diabetes, the 12 mg group lost a mean 24.2% at 48 weeks versus 2.1% with placebo. This was a controlled trial, not a prediction of an individual's response.
1The September 29, 2026 TRIUMPH-1 paper reports 25.0% mean weight reduction with 12 mg versus 3.9% with placebo at 80 weeks (treatment-regimen estimand). The earlier 28.3% sponsor headline used a different efficacy analysis; these estimates should not be interchanged.
52Phase 3 randomized 80-week trial published September 29, 2026; dose groups were 4, 9 and 12 mg weekly versus placebo. Trial estimates must be identified by estimand rather than presented as guaranteed weight loss.
Phase 3 randomized trial32Sponsor reported 28.3% mean weight reduction at 80 weeks for 12 mg using its efficacy estimand; not approval or a forecast for individuals.
Sponsor phase 3 report33Weight management research. Human trials found substantial weight loss in adults with obesity without diabetes.15
Type 2 diabetes research. Early human development includes glucose-control studies.4
Weight. Weight reduction, appetite and maintenance research.31
Diabetes. Glycemic control and insulin sensitivity.31
Other outcomes. Lipids, BP, liver fat and obesity-related complications; outcome-specific evidence varies.31
Pep-Pedia describes interest in appetite and weight changes, and explicitly distinguishes community starting amounts from the TRIUMPH trial schedule.8
A secondary protocol description, not a clinical recommendation or a representative survey. Dose, product identity, other compounds and outcome reporting are not independently verified.
The targeted check identified relevant additional literature or current regulatory information; checked findings are separated from retained bibliography-only references.
AI-prepared summaries. Independent medical editorial review is pending.
Results were not available when checked. This does not mean there were no responses.
Original sources and review status. Open a reference to read its summary.
Randomized obesity trial: the 12 mg group averaged 24.2% weight loss at 48 weeks; placebo averaged 2.1%. GI effects were common.
In 338 adults with obesity or overweight without diabetes, the 12 mg group lost a mean 24.2% at 48 weeks versus 2.1% with placebo. This was a controlled trial, not a prediction of an individual's response.
Pep-Pedia bibliography · Checked 2026-10-12
Sponsor announcement reports 28.3% mean weight reduction at 80 weeks with 12 mg. It is a topline report, not an independent review.
The September 29, 2026 TRIUMPH-1 paper reports 25.0% mean weight reduction with 12 mg versus 3.9% with placebo at 80 weeks (treatment-regimen estimand). The earlier 28.3% sponsor headline used a different efficacy analysis; these estimates should not be interchanged.
Pep-Pedia bibliography · Checked 2026-10-12
FDA identifies retatrutide as unapproved and raises concerns about products marketed directly to consumers.
Weekly subcutaneous retatrutide was studied in adults with type 2 diabetes; the reported half-life was approximately six days.
Published September 29, 2026. The treatment-regimen estimate differs from the earlier sponsor efficacy headline.
The September 29, 2026 TRIUMPH-1 paper reports 25.0% mean weight reduction with 12 mg versus 3.9% with placebo at 80 weeks (treatment-regimen estimand). The earlier 28.3% sponsor headline used a different efficacy analysis; these estimates should not be interchanged.
Original analytical work describes the 39-residue backbone and lipidated side chain. Its small observational exposure series is not an efficacy trial.
Weekly subcutaneous retatrutide was studied in adults with type 2 diabetes; the reported half-life was approximately six days.
Pep-Pedia bibliography · Checked 2026-10-12
Accessed October 12, 2026. Reports commonly discussed protocols; these schedules are unvalidated descriptions, not evidence of safety or efficacy.
Catalog lists a 10 mg lyophilized research vial. These are seller label examples, not verified contents, market-frequency estimates or supplier endorsements.
Chemical reference for the peptide formula and 4731.3 formula weight; the sodium counterion quantity is variable. Not a clinical preparation guide.
Pep-Pedia reports: The secondary page reports TRIUMPH-2/3 topline weight and glycemic outcomes. Its cardiovascular interval crosses no effect, and the cited release needs confirmation.
Reported population / model
Human
Reported study details
4-12mg weekly · 80 weeks · TRIUMPH-2 20.8% weight / 1.6% A1C; TRIUMPH-3 22.6% weight
Reported by Pep-Pedia; the linked publication, design, doses and result have not been independently verified here.
Read the Pep-Pedia report ↗Pep-Pedia reference card; original summary of its reported findings · Checked 2026-10-12
Pep-Pedia reports: The source reports sleep-apnea and knee-pain substudy changes from a conference presentation; it does not provide a verified primary analysis here.
Reported population / model
Human
Reported study details
TRIUMPH-1 substudies · OSA AHI reduced 60.6%; WOMAC pain reduced 73.1%
Reported by Pep-Pedia; the linked publication, design, doses and result have not been independently verified here.
Read the Pep-Pedia report ↗Pep-Pedia reference card; original summary of its reported findings · Checked 2026-10-12
Pep-Pedia reports: The source reports up to 16.8% weight loss and roughly two HbA1c points in early diabetes, with gastrointestinal events and treatment discontinuations.
Reported population / model
Human
Reported study details
4-12mg weekly · 40 weeks · 16.8% weight loss, 2.0% A1C reduction
Reported by Pep-Pedia; the linked publication, design, doses and result have not been independently verified here.
Read the Pep-Pedia report ↗Pep-Pedia reference card; original summary of its reported findings · Checked 2026-10-12
Pep-Pedia reports: The source reports 28.7% weight loss at 12 mg alongside knee-pain improvement, with substantial discontinuation and dysesthesia rates.
Reported population / model
Human
Reported study details
9-12mg weekly · 68 weeks · 28.7% weight loss (71.2 lbs)
Reported by Pep-Pedia; the linked publication, design, doses and result have not been independently verified here.
Read the Pep-Pedia report ↗Pep-Pedia reference card; original summary of its reported findings · Checked 2026-10-12
Pep-Pedia reports: A liver-fat substudy reportedly reduced liver fat by about 82%, with frequent normalization at higher doses; this surrogate is distinct from clinical liver outcomes.
Reported population / model
Human
Reported study details
8-12mg weekly · 24 weeks · 82% liver fat reduction
Reported by Pep-Pedia; the linked publication, design, doses and result have not been independently verified here.
Read the Pep-Pedia report ↗Pep-Pedia reference card; original summary of its reported findings · Checked 2026-10-12
Pep-Pedia reports: This is a planned cardiovascular/kidney outcome trial; the card gives no completed outcome result and its stated regimen requires registry confirmation.
Reported population / model
Human
Reported study details
8mg weekly · 248 weeks · 10,000 participants with ASCVD
Reported by Pep-Pedia; the linked publication, design, doses and result have not been independently verified here.
Read the Pep-Pedia report ↗Pep-Pedia reference card; original summary of its reported findings · Checked 2026-10-12
Pep-Pedia reports: The phase 2 diabetes study reportedly improved both weight and HbA1c; the card uses different glycemic maxima, so dose/estimand details matter.
Reported population / model
Human
Reported study details
0.5-12mg weekly · 36 weeks · 16.9% weight loss, -2.02% HbA1c
Reported by Pep-Pedia; the linked publication, design, doses and result have not been independently verified here.
Read the Pep-Pedia report ↗Pep-Pedia reference card; original summary of its reported findings · Checked 2026-10-12
Pep-Pedia reports: Early human work characterized dose-related exposure and an approximately six-day half-life; a small early trial cannot establish comprehensive safety.
Reported population / model
Human
Reported study details
Single ascending dose · 12 weeks · Established 6-day half-life
Reported by Pep-Pedia; the linked publication, design, doses and result have not been independently verified here.
Read the Pep-Pedia report ↗Pep-Pedia reference card; original summary of its reported findings · Checked 2026-10-12
Listed in Pep-Pedia’s bibliography; the linked publication and its findings have not been independently verified in this pass.
Pep-Pedia bibliography · Checked 2026-10-12
Listed in Pep-Pedia’s bibliography; the linked publication and its findings have not been independently verified in this pass.
Pep-Pedia bibliography · Checked 2026-10-12
Listed in Pep-Pedia’s bibliography; the linked publication and its findings have not been independently verified in this pass.
Pep-Pedia bibliography · Checked 2026-10-12
Listed in Pep-Pedia’s bibliography; the linked publication and its findings have not been independently verified in this pass.
Pep-Pedia bibliography · Checked 2026-10-12
Listed in Pep-Pedia’s bibliography; the linked publication and its findings have not been independently verified in this pass.
Pep-Pedia bibliography · Checked 2026-10-12
Lists a single vial labeled 24 mg of lyophilized retatrutide. Checked October 12, 2026. Used only to document the labeled amount; contents, supplier quality and suitability for human use were not independently verified.
Lists 5, 10, 12, 15, 20, 24, 25, 30, 40, 50 and 60 mg vial labels. Checked October 12, 2026. Used only as packaging evidence, not to validate the seller’s preparation, storage or medical claims.
Lists 10, 12, 15, 20, 30 and 50 mg vial options. Checked October 12, 2026. Nominal label amounts and the seller’s reported analytical results are distinct; neither the contents nor testing were independently verified here.
Lists 10, 20, 30, 40 and 60 mg research vial options. Checked October 12, 2026. This establishes listed packaging amounts only, not market prevalence, product quality or fitness for injection.
FDA describes U-100 syringe conversion, including 5 units = 0.05 mL, and reports errors caused by confusing units, volume and concentration. The alert concerns compounded semaglutide; it supports the measurement explanation, not retatrutide preparation or dosing. Checked October 12, 2026.
Sequence and modifications checked October 12, 2026. Aib at 2 and 20; αMeL = alpha-methylleucine at 13; K* at 17 carries the lipidated side chain. C-terminal amide. Backbone positions include the modifications described in the systematic identity.
Lists a half-life of 6 days and a peak time of 1 day. Stated attribution: Phase 2 Clinical Trial Data (Eli Lilly). This value is reported by a secondary reference. The stated attribution has not been independently verified as a route- and formulation-matched human PK measurement. Five half-lives is not complete clearance, and the source’s “cleared” value is not used as a measured endpoint.
Secondary reference page checked; the underlying quantitative claim is not independently confirmed. · Checked 2026-10-12
Source page checked across available routes. Protocols, cycles, storage, mechanisms and pairing claims are secondary reports; checking the page does not independently validate those claims. Original concise summaries are used here.
Content coverage audit · Checked 2026-10-12
Phase 3 randomized 80-week trial published September 29, 2026; dose groups were 4, 9 and 12 mg weekly versus placebo. Trial estimates must be identified by estimand rather than presented as guaranteed weight loss.
Phase 3 randomized 80-week trial published September 29, 2026; dose groups were 4, 9 and 12 mg weekly versus placebo. Trial estimates must be identified by estimand rather than presented as guaranteed weight loss.
Additional primary-source check · Checked 2026-10-12
Sponsor reported 28.3% mean weight reduction at 80 weeks for 12 mg using its efficacy estimand; not approval or a forecast for individuals.
Sponsor reported 28.3% mean weight reduction at 80 weeks for 12 mg using its efficacy estimand; not approval or a forecast for individuals.
Additional primary-source check · Checked 2026-10-12