Is Retatrutide considered natty?

Retatrutide is classified as not natty. It is prohibited by WADA and banned by most natural bodybuilding federations. Use places an athlete in the enhanced category.

Is Retatrutide on the WADA prohibited list?

Yes, Retatrutide appears on the WADA prohibited list and is banned in competition and out-of-competition.

How is Retatrutide administered?

Retatrutide is typically administered via: subcutaneous injection. Dosage and administration protocols vary; see the Dosage section for details.

Retatrutide - Retapedia | Natty or Not?

Medical disclaimer. This article is for informational purposes only and does not constitute medical advice. Consult a qualified clinician before considering any compound discussed below. See Retapedia : Medical disclaimer.

Retatrutide
Available for Research
10mg Retatrutide Bacteriostatic Water Reconstitution Solution 10ml
Structure of Retatrutide. 39-aa GLP-1/GIP/glucagon triagonist with Aib substitutions, γGlu–C20 diacid lipidation, and a C-terminal amide. Source: Wikimedia Commons.
Identification
Class	Modified peptide
PubChem CID	171390338
Other names	Retatrutide · GIP/GLP-1/Glucagon triple agonist
Trade names	Retatrutide
Administration
Routes	Subcutaneous injection
Status
Verdict	Not natty
WADA	Prohibited^[7]
Article meta
Slug	`retatrutide`
Last edited	August 4, 2026
Tags	fat loss, weight loss, triple agonist, metabolic health, diabetes, subcutaneous

Retatrutide (also known as Retatrutide or GIP/GLP-1/Glucagon triple agonist) is a performance-enhancing peptide studied for its effects on fat loss, weight loss, triple agonist. Triple receptor agonist (GLP-1/GIP/glucagon) with superior weight loss (24% in trials) vs tirzepatide/semaglutide. Phase 3 trials. Not FDA-approved.

Retatrutide (LY-3437943) is an investigational triple receptor agonist developed by Eli Lilly that simultaneously activates GLP-1 (glucagon-like peptide-1), GIP (glucose-dependent insulinotropic polypeptide), and glucagon receptors. This unique triple-agonist mechanism promotes superior weight loss compared to single or dual agonists by combining appetite suppression, enhanced insulin secretion, improved glucose homeostasis, and increased energy expenditure. Phase 2 trials demonstrated exceptional efficacy with 24.2% mean weight reduction at 48 weeks (12mg dose), significantly outperforming tirzepatide (~21%) and semaglutide (~15%).

Natty status

Retatrutide is classified as not natty. It is prohibited by WADA and most natural bodybuilding federations. Use places the athlete in the enhanced category. See § Natty status.

Contents [hide]

1 Overview
2 Mechanism of action
3 Reported effects
4 Dosage and administration
5 Natty status
6 Research
7 Related compounds
8 References
9 External links

Overview

Beyond weight loss, retatrutide shows promise for treating type 2 diabetes, metabolic-associated steatohepatitis (MASH/NAFLD), with 90% of patients achieving liver fat normalization at highest doses.

Currently advancing through Phase 3 TRIUMPH clinical trials (5,800+ participants) for obesity, obstructive sleep apnea, and knee osteoarthritis.

Not FDA-approved; investigational use only, and because it has no regulatory approval for human therapeutic use anywhere it is prohibited by WADA at all times under category S0 (non-approved substances).

Common side effects include dose-dependent gastrointestinal issues (nausea, vomiting, diarrhea) that typically diminish over time, plus modest heart rate increases (5-10 bpm).

Gradual dose titration over 12-16 weeks minimizes adverse events, with 16% discontinuation rate at highest dose versus 6% at lowest dose.

Mechanism of action

Triple agonist that curbs appetite and raises energy expenditure for 24% weight loss. Improves blood sugar, lowers blood pressure, and normalizes liver fat. Investigational; not FDA-approved.

Reported effects

Effects reported in the literature and from preclinical models include:

At the 12 mg maximal weekly dose, retatrutide reduced total body weight by 24.2% at 48 weeks, with 63% of participants losing at least 20% of body weight and a 23.2% reduction in fat mass. ^[2]^[3] Phase II
In patients with type 2 diabetes, retatrutide produced an absolute HbA1c reduction of 2.02%, with 27% of participants reaching normoglycemia below 5.7%. ^[2] Phase II
Retatrutide ranked best for weight loss among 15 incretin-based therapies in a Bayesian network meta-analysis of 102 randomized trials in type 2 diabetes. ^[6] Phase II
Retatrutide achieved an 82.4% relative reduction in hepatic fat and normalized liver fat in 86% of patients with metabolic dysfunction-associated steatotic liver disease. ^[2]^[4] Phase II
Pooled randomized controlled trial data show retatrutide lowers systolic blood pressure by 6.79 mmHg and diastolic blood pressure by 2.46 mmHg, and reduces total cholesterol, LDL-C, and triglycerides without changing HDL-C. ^[5]^[2] Phase II
Retatrutide reduced body weight, alanine aminotransferase, hepatic triglycerides, and hepatic inflammatory markers in a diet-induced steatohepatitis mouse model. ^[1] Preclinical

Evidence grades: FDA approvedApproved (non-US)Phase IIIPhase IIPhase IPreclinicalAnecdotal

Dosage and administration

⚠

Dosage information is included for encyclopedic purposes only. Retapedia does not provide medical advice. See Retapedia : Medical disclaimer.

General

Phase 2 protocol - Week 1-4: 2mg once weekly (subcutaneous)
Phase 2 protocol - Week 5-8: 4mg once weekly
Phase 2 protocol - Week 9-12: 8mg once weekly
Phase 2 protocol - Week 13+: 12mg once weekly (maximum dose)
Lower starting dose (2mg vs 4mg) reduces GI side effects

Alternative titration

1mg, then 2mg, then 4mg, then 6mg, then 8mg (escalate every 4 weeks)

Maintenance range

4-12mg weekly depending on response and tolerability

Natty status

See also: Peptide § Natty status

Retatrutide is classified as not natty. It appears on the WADA prohibited list and is banned by major natural bodybuilding federations.^[7] Use of this compound places the athlete in the enhanced category rather than the natural category in competitive contexts.