Evidence strength for the context described on this page.
PEPTIDE ATLAS / METABOLIC & FAT LOSS / RETATRUTIDE
InvestigationalEarly human
Retatrutide
ALSO KNOWN ASLY3437943 · triple agonist
A triple GIP/GLP-1/glucagon agonist in clinical development—not an approved drug.
01CATEGORYMetabolic & fat loss
02REGULATORY STATUSInvestigational
03COMMON ROUTESubcutaneous injection in registered clinical trials
04DOSE BASISHuman research only
HOW TO USE THIS PAGE
Read the profile in the order that protects the decision.
- 01Verify what it is
Confirm the exact molecule, route, regulatory lane and actual human evidence.
- 02Read limits before dose
Unsupported claims, contraindications and uncertainty come before any protocol.
- 03Build the monitoring plan
Define the target, baseline checks, reassessment point and stop rules with a qualified clinician.
This peptide does not have an FDA-approved product or dose for the claims described here. Research dosing and vendor protocols are not consumer prescribing guidance.
RESEARCH PASSPORT
The five facts to know first.
REVIEWED
JULY 2026
Status is product-, formulation- and indication-specific.
Trial, label or reported-practice basis is always named.
Official labels, regulators, trials and indexed literature where available.
Peptide hormones, growth factors and related substances may be prohibited.
Check Global DRO ↗OVERVIEW
What Retatrutide is.
An investigational peptide being studied for obesity and related metabolic disease. Products sold online as retatrutide are not FDA-approved clinical-trial supplies.
HOW IT IS THOUGHT TO WORK
Activates GIP and GLP-1 receptors while also engaging the glucagon receptor, aiming to combine appetite reduction with altered energy expenditure.
EFFECTS & EVIDENCE
What the evidence supports—and what it does not.
- Large average weight reductions in phase 2 research
- Ongoing phase 3 programs are testing efficacy, durability and safety
- Long-term benefit-risk outside trials
- Safety of online or compounded products
- An approved dose, product specification or consumer protocol
Evidence grade: Early human. For an approved drug, “high” refers only to its labeled indication—not every off-label or wellness claim.
DOSAGE CONTEXT
Best available dosing range.
Human research onlyBest human-research range: 1, 4, 8 or 12 mg subcutaneously once weekly in phase 2, with stepwise escalation for higher targets. Phase 3 programs use protocol-defined weekly targets such as 4, 9 or 12 mg. Retatrutide remains investigational; these are authenticated trial doses, not a prescription or a basis for using products sold online.
BEST AVAILABLE GENERIC RANGE
Men and women.
The basis is named above. Reported-use ranges describe what clinics or communities publish; they are not proof of safety, efficacy, legality or product quality.
- Schedule in that source context
- Once weekly for 48 weeks in phase 2, with stepwise escalation for higher target-dose groups; current phase 3 schedules are protocol-controlled.
- How to interpret it
- This is a research range, not clinic guidance. Lilly states retatrutide remains investigational and should only be received in a legitimate clinical trial. Products claiming to be retatrutide outside trials are not authenticated trial supply.
ACTUAL HUMAN DOSES REPORTED IN THE RECORD
Research regimens may use different routes, diagnoses, formulations and monitoring. They cannot automatically be converted into a general protocol.
- Phase 2 obesity trial: target doses of 1, 4, 8 and 12 mg once weekly for 48 weeks; higher target groups used gradual escalation.
- Phase 3 obesity programs: protocol targets include 4, 9 and 12 mg once weekly.
- Route
- Subcutaneous injection in registered clinical trials
- Duration
- Investigational; defined by trial protocol
- Men & women
- No sex-specific dose was established in trials. Pregnancy and reproductive plans require trial-team review.
Clinician verification required. Always double-check the exact molecule or salt, concentration, route, volume, schedule, indication, patient-specific contraindications, interactions and applicable law with the prescribing clinician and dispensing pharmacy. A disclaimer does not make an unapproved product FDA-approved, and a reported-use range is not a prescription.
MONITORING
What should be tracked.
- Only within a registered trial with protocol-defined safety monitoring
SAFETY
Risks, red flags and reasons to avoid it.
- GI adverse effects and heart-rate changes observed in research
- Unknown long-term effects
- Counterfeit, contamination and dosing risks outside trials
- Products marketed for consumer sale
- Self-injection outside a legitimate clinical trial
- Assuming similarity to tirzepatide means interchangeability
Stop and seek careGet urgent medical help for trouble breathing, facial or throat swelling, chest pain, fainting, severe persistent abdominal pain, neurologic changes, severe hypoglycemia, uncontrolled vomiting or a prolonged painful erection.
CLINICIAN VISIT CHECKLIST
Six questions worth bringing with you.
Molecule or analog, salt, concentration, route, manufacturer or compounder, lot and beyond-use date.
Name the diagnosis or target, how it will be measured and the realistic time to reassess.
Ask how it compares with FDA-approved, lower-risk or better-studied alternatives.
Label, human trial, specialty guideline or clinic convention—and whether that route and formulation match.
Baseline checks, follow-up measures, interactions, pregnancy considerations and symptoms that mean stop.
Pharmacy license, prescription, identity/potency testing, sterility controls and who handles a product complaint.
Do not improvise reconstitution or convert “units” without the exact concentration. Mixing, storage and beyond-use instructions are product-specific; confirm them with the dispensing pharmacy.
PRIMARY SOURCES
Read the record yourself.
We prioritize official prescribing information, FDA regulatory material, registered trials and indexed biomedical literature. A source supports the specific statement beside it—not every claim made about the molecule.
PRODUCTS & TREATMENT ACCESS
There is no product we can responsibly recommend.
Legitimate access is through registered clinical research. FDA has cited online retatrutide products as unapproved new drugs.
Phase 2 results are not market authorization. A research-chemical vendor cannot recreate trial oversight, manufacturing controls or authenticated supply.
Evidence before affiliate revenue.
We do not rank or sell unapproved research peptides. Use the Atlas to discuss safer, evidence-backed alternatives with a qualified clinician.
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