Retatrutide
Also known as LY3437943
Retatrutide is an investigational triple hormone receptor agonist that activates GLP-1, GIP, and glucagon receptors. In mid-stage clinical trials it produced some of the largest average body-weight reductions reported for an injectable weight-management agent to date. It is not yet approved by regulatory agencies and remains under study in late-stage clinical trials. Research to date is limited to controlled trial populations, and long-term safety and outcome data are still being gathered. It should not be considered an approved treatment, and any use outside of a clinical trial or licensed prescriber's supervision is not supported by current evidence.
Reported benefits
- Associated with substantial reductions in body weight in clinical trial participants
- May improve markers of glycemic control
- Combined incretin/glucagon activity may support fat oxidation
- Once-weekly dosing schedule in studies to date
How it works
Retatrutide binds and activates three separate incretin-related receptors: GLP-1, GIP, and the glucagon receptor. Combined GLP-1/GIP activity slows gastric emptying and increases satiety signaling, while added glucagon receptor activity is believed to raise energy expenditure and support hepatic fat metabolism. This triple-receptor approach is proposed to produce greater metabolic effect than single- or dual-receptor agonists, though the relative contribution of each receptor pathway in humans is still being characterized.
Dosing ranges
| Tier | Dose | Frequency |
|---|---|---|
| Low | 2 mg | once weekly |
| Moderate | 4 mg | once weekly |
| High | 12 mg | once weekly |
Estimate your dose
Dose estimator
Educational estimate for Retatrutide, scaled to body size. Not medical advice.
Read before using
This tool produces a rough, educational estimate by scaling commonly-published research ranges to lean body mass. It is not a prescription, medical advice, or a substitute for a licensed clinician. Most peptides use fixed dosing, not weight-based dosing. Individual needs vary. You are solely responsible for how you use this information.
Mixing & syringe units
Target dose follows the estimate above. Change it there, or edit it directly below.
Reconstitution calculator
How much water to add and how many insulin-syringe units to draw for Retatrutide. Educational only.
Draw to this mark
80units
= 0.8 mL for a 4 mg dose
Concentration
5 mg/mL
Doses per vial
2
A U-100 syringe reads 100 units per mL. This is a reconstitution math helper only, not a prescription or dosing advice. Verify every calculation and consult a qualified healthcare provider.
Possible side effects
Stacking notes
Not established; combining with other incretin-based agents is not supported by published research and may increase gastrointestinal side effects.
Common protocols
Common questions
What is Retatrutide used for?
Retatrutide is an investigational triple hormone receptor agonist that activates GLP-1, GIP, and glucagon receptors. In mid-stage clinical trials it produced some of the largest average body-weight reductions reported for an injectable weight-management agent to date. It is not yet approved by regulatory agencies and remains under study in late-stage clinical trials. Research to date is limited to controlled trial populations, and long-term safety and outcome data are still being gathered. It should not be considered an approved treatment, and any use outside of a clinical trial or licensed prescriber's supervision is not supported by current evidence. Reported benefits include associated with substantial reductions in body weight in clinical trial participants, may improve markers of glycemic control, combined incretin/glucagon activity may support fat oxidation.
What is a typical Retatrutide dose?
Reported ranges run 2-12 mg. A low protocol is 2 mg once weekly, and a high protocol is 12 mg once weekly. This is reference information, not a dosing recommendation.
What is the half life of Retatrutide?
Approximately 17 days in trial pharmacokinetic reports, consistent with once-weekly dosing. That is what sets the dosing frequency, and it is why the timing guidance is weekly · same day, any time.
How is Retatrutide administered?
Subcutaneous: into fat, under the skin.
How long is a Retatrutide cycle?
Continuous use with gradual up-titration over several months in trial protocols on, followed by Not established outside of trial discontinuation; no standard off-cycle described in published research off. Dose increases are typically spaced several weeks apart to reduce gastrointestinal side effects.
What are the side effects of Retatrutide?
Reported side effects include nausea, vomiting, and diarrhea, especially during dose escalation, decreased appetite, potential for gallbladder-related events, injection-site reactions, theoretical thyroid c-cell risk based on the glp-1 drug class. Evidence level for this compound is moderate evidence.
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Educational use only, not medical advice. This profile is provided for research and educational purposes. Retatrutide may be a research compound or a prescription medication; nothing here is intended to diagnose, treat, cure, or prevent any disease. Dosing figures reflect commonly-published research ranges, not a prescription. Consult a qualified healthcare provider before making any health decision. Read the full disclaimer →