Retatrutide Dosage Guide

Investigational triple agonist (GLP-1/GIP/Glucagon) — titration schedules from Phase 2 trial data, reconstitution, injection technique, comparison to Semaglutide & Tirzepatide, and safety.

Compiled by PeptideWiki Editorial Team·Last reviewed February 24, 2026

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Retatrutide

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What Is Retatrutide?

Investigational Drug Warning: Retatrutide (LY3437943) is NOT FDA-approved. It is an investigational compound currently in Phase 3 clinical trials. All dosing information in this guide is derived from a single Phase 2 trial and community protocols — not from an approved drug label. Using an unapproved investigational drug carries inherent risk. Consult a healthcare provider before using any research compound.

Retatrutide (LY3437943) is an investigational triple hormone receptor agonist developed by Eli Lilly. It is the first compound designed to simultaneously activate three incretin and metabolic hormone receptors: GLP-1 (glucagon-like peptide-1), GIP (glucose-dependent insulinotropic polypeptide), and glucagon. This triple mechanism distinguishes it from single agonists like Semaglutide (GLP-1 only) and dual agonists like Tirzepatide (GLP-1 + GIP).

The addition of glucagon receptor agonism is the novel element. While GLP-1 and GIP suppress appetite and enhance insulin secretion, glucagon increases energy expenditure, promotes hepatic fat oxidation, and stimulates thermogenesis — mechanisms that drive additional weight loss beyond what GLP-1/GIP alone can achieve. In the Phase 2 trial, Retatrutide at 12 mg per week produced the largest weight loss ever reported in an obesity drug trial: 24.2% of body weight at 48 weeks.

Use our Peptide Dosage to calculate your exact dose based on vial size and concentration.

Key Characteristics:

Triple receptor agonist — simultaneously activates GLP-1, GIP, and glucagon receptors — the first compound to target all three
GLP-1 receptor — suppresses appetite, slows gastric emptying, enhances glucose-dependent insulin secretion
GIP receptor — improves insulin sensitivity, enhances lipid metabolism, and complements GLP-1 effects on insulin secretion
Glucagon receptor (novel) — increases energy expenditure, promotes hepatic fat oxidation, stimulates thermogenesis — the key differentiator from Semaglutide and Tirzepatide
Once-weekly injection — administered subcutaneously once per week with an estimated half-life of approximately 6 days
Investigational status — developed by Eli Lilly; currently in Phase 3 trials (TRIUMPH program). NOT FDA-approved. Approval not expected before late 2026–2027

For a complete overview of its mechanism and research, see our full Retatrutide profile. New to peptides? Start with the Beginner's Guide to Peptides.

How Retatrutide Dosage Is Determined

Unlike most peptides in this guide, Retatrutide dosing is derived directly from a controlled clinical trial rather than from animal studies and community extrapolation. The Phase 2 trial provides the most rigorous dosing data available for this compound.

Phase 2 Trial (Jastreboff et al., NEJM 2023)

The pivotal Phase 2 trial enrolled 338 adults with obesity (BMI ≥30) or overweight (BMI ≥27 with a weight-related condition) in a randomized, double-blind, placebo-controlled study. Participants were assigned to placebo or one of four Retatrutide dose groups (1 mg, 4 mg, 8 mg, or 12 mg weekly) for 48 weeks. All active groups used a titration schedule to reach their target dose.

Results by Dose Group

Group	Mean Weight Loss	≥5% Loss	≥10% Loss	≥15% Loss
Placebo	−2.1%	27%	9%	5%
1 mg	−8.7%	64%	34%	19%
4 mg	−17.1%	93%	75%	57%
8 mg	−22.8%	100%	93%	83%
12 mg	−24.2%	100%	93%	83%

Notably, 100% of participants in both the 8 mg and 12 mg groups lost at least 5% of their body weight — a threshold rarely achieved in obesity pharmacotherapy. The 12 mg group's 24.2% mean weight loss is the largest reported for any anti-obesity drug in a clinical trial.

Dosing information in this guide is derived from published research and community protocols.

Retatrutide Titration Schedule

Retatrutide requires a gradual dose escalation (titration) over the first 12 weeks to minimize gastrointestinal side effects. The following schedules are derived from the Phase 2 trial protocol. All doses are administered once weekly via subcutaneous injection.

12 mg Target (Maximum Dose)

Period	Weekly Dose	Duration	Purpose
Step 1	2 mg	Weeks 1–4	Initial tolerance assessment; GI acclimation
Step 2	4 mg	Weeks 5–8	First escalation; meaningful weight loss begins
Step 3	8 mg	Weeks 9–12	Second escalation; approaching therapeutic range
Maintenance	12 mg	Week 13+	Full therapeutic dose; sustained weight loss

8 mg Target

Period	Weekly Dose	Duration
Step 1	2 mg	Weeks 1–4
Step 2	4 mg	Weeks 5–8
Maintenance	8 mg	Week 9+

4 mg Target

Period	Weekly Dose	Duration
Step 1	2 mg	Weeks 1–4
Maintenance	4 mg	Week 5+

Community note: Some users start even lower than the trial protocol — at 0.5–1 mg for the first 1–2 weeks — before beginning the 2 mg starting dose. This ultra-low start is not from the clinical trial but is used anecdotally to further reduce initial GI side effects. If you do this, consider extending each titration step by 1–2 weeks accordingly.

Do not skip titration. Starting at the full target dose (8 mg or 12 mg) without titrating is the single most common mistake. It leads to severe nausea, vomiting, and diarrhea that may force discontinuation. The titration schedule is mandatory — not optional.

Retatrutide vs Semaglutide vs Tirzepatide

Retatrutide is often compared to Semaglutide and Tirzepatide — the two leading GLP-1-based obesity treatments. The table below summarizes key differences. Note that cross-trial comparisons have important limitations and should not be treated as direct head-to-head evidence.

Feature	Retatrutide	Semaglutide	Tirzepatide
Receptors	GLP-1 + GIP + Glucagon	GLP-1 only	GLP-1 + GIP
FDA Status	Not approved (Phase 3)	Approved (Wegovy / Ozempic)	Approved (Zepbound / Mounjaro)
Max Dose	12 mg/week	2.4 mg/week	15 mg/week
Frequency	Once weekly	Once weekly	Once weekly
Peak Weight Loss (trial)	24.2% at 48 weeks	~15–17% at 68 weeks	~22.5% at 72 weeks
Half-life	~6 days	~7 days	~5 days
Titration Period	12 weeks	16–20 weeks	16–20 weeks
Availability	Research / compounding only	Prescription (branded)	Prescription (branded)

Cross-trial comparison caveat: The weight loss figures above come from different trials with different populations, durations, and protocols. They are indicative but not equivalent to a head-to-head study. Retatrutide's 48-week timeframe is shorter than the 68–72 week timeframes for Semaglutide (STEP trials) and Tirzepatide (SURMOUNT trials), and weight loss had not yet plateaued in the Retatrutide trial.

For detailed dosing protocols for these FDA-approved alternatives, see our Semaglutide Dosage Guide and Tirzepatide Dosage Guide.

Calculate Your Retatrutide Dose

Retatrutide from compounding sources is supplied as a lyophilized (freeze-dried) powder, typically in 5 mg or 10 mg vials. You reconstitute it with bacteriostatic water, then draw your dose using an insulin syringe. The concentration depends on how much water you add to the vial.

Worked Example:

Vial size: 10 mg (10,000 mcg) of Retatrutide
Bacteriostatic water added: 2 mL
Concentration: 10 mg ÷ 2 mL = 5.0 mg per mL
Target dose: 4 mg
Volume to draw: 4 ÷ 5 = 0.8 mL = 80 units on an insulin syringe

Quick Reference — 10 mg Vial

Bac Water Added	Concentration	2 mg Dose	4 mg Dose	8 mg Dose	12 mg Dose
1 mL	10 mg/mL	20 units	40 units	80 units	120 units*
2 mL	5 mg/mL	40 units	80 units	160 units*	240 units*

* Exceeds 1 mL syringe capacity. Doses marked with an asterisk exceed 100 units (1 mL), the capacity of a standard insulin syringe. For these doses, you must either: (a) split the dose into two injections using two syringes, or (b) use less bacteriostatic water to achieve a higher concentration. For the 12 mg dose, using 1 mL of bac water (10 mg/mL) requires only 120 units — still exceeding a 1 mL syringe. Consider using a 3 mL syringe with a detachable needle for large volume doses.

Quick Reference — 5 mg Vial

Bac Water Added	Concentration	2 mg Dose	4 mg Dose
0.5 mL	10 mg/mL	20 units	40 units
1 mL	5 mg/mL	40 units	80 units
2 mL	2.5 mg/mL	80 units	160 units*

A 5 mg vial is best suited for the titration phase (2–4 mg doses). For the full 8 mg or 12 mg maintenance dose, a 10 mg or larger vial is more practical.

Skip the Math — Use Our

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How to Reconstitute Retatrutide

Retatrutide from compounding sources comes as a lyophilized (freeze-dried) powder. There are no branded pre-filled pens available — reconstitution with bacteriostatic water is required before injection. The process is standard for peptide reconstitution.

Compounded product warning: Unlike FDA-approved Semaglutide (Wegovy) or Tirzepatide (Zepbound), which come in pre-filled pens with precise dosing, compounded Retatrutide requires manual reconstitution and dose calculation. Errors in reconstitution directly affect the dose you receive. Follow the steps below carefully.

Supplies Needed:

Retatrutide lyophilized vial (5 mg or 10 mg)
Bacteriostatic water (BAC water) — contains 0.9% benzyl alcohol as preservative
Insulin syringes (29–31 gauge, 0.5 mL or 1 mL) for injection
Alcohol swabs (70% isopropyl alcohol)
Clean, flat workspace
Optional: larger syringe (1–3 mL) for drawing bacteriostatic water or for high-dose injections exceeding 1 mL

Steps

Wash Hands & Prepare Workspace

Wash hands thoroughly with soap and water. Lay out supplies on a clean surface: Retatrutide vial, bacteriostatic water, insulin syringe, and alcohol swabs.

Remove the Vial Caps

Flip off the plastic caps from both the Retatrutide vial and the bacteriostatic water vial. Swab both rubber stoppers with alcohol pads and let them air-dry for 10–15 seconds.

Draw Bacteriostatic Water

Using a fresh insulin syringe, draw your desired volume of bacteriostatic water. For a 10 mg vial, 2 mL is standard (yields 5.0 mg per mL).

Add Water to the Peptide Calculator Vial

Insert the needle into the Retatrutide vial through the rubber stopper. Angle the needle so the water runs down the inside glass wall — never squirt directly onto the powder cake. Release the plunger slowly.

Dissolve Gently

Remove the syringe. Let the vial sit for 1–2 minutes, then gently swirl or roll between your palms until the powder is fully dissolved. The solution should be clear and colorless. Never shake.

Label & Refrigerate

Write the reconstitution date and concentration on the vial. Store refrigerated at 2–8°C. Use within 28–30 days.

Storage

Unreconstituted (powder): Store refrigerated (2–8°C) for maximum shelf life; room temperature is acceptable for short periods (weeks) but reduces potency over time
Reconstituted (in bacteriostatic water): Must be refrigerated at 2–8°C; use within 28–30 days
Do not freeze: Freezing reconstituted Retatrutide can damage the peptide structure through ice crystal formation
Protect from light and heat — keep the vial in its box or wrapped in foil, away from direct sunlight and temperatures above 25°C

For a detailed visual walkthrough, see our Reconstitution Guide.

Retatrutide Dosage by Goal

All Phase 2 trial data is for weight loss in adults with obesity or overweight. Dosage recommendations by goal below are based on the trial results and emerging community experience.

Maximum Weight Loss (12 mg/week)

The highest dose tested in the Phase 2 trial. Produced 24.2% mean weight loss at 48 weeks — the largest ever reported for an obesity pharmacotherapy. Requires the full 12-week titration protocol.

Target dose: 12 mg subcutaneously once weekly
Titration: 2 mg → 4 mg → 8 mg → 12 mg over 12 weeks
Duration: 48+ weeks (weight loss had not plateaued at 48 weeks in the trial)
GI side effects: Most common at this dose; nausea, diarrhea, and vomiting occur frequently during titration but generally improve

Moderate Weight Loss (8 mg/week)

Produced 22.8% mean weight loss — only 1.4 percentage points less than the 12 mg group but with somewhat fewer GI side effects. A strong option for those seeking efficacy with slightly better tolerability.

Target dose: 8 mg subcutaneously once weekly
Titration: 2 mg → 4 mg → 8 mg over 8 weeks
Duration: 48+ weeks
Notes: 100% of participants in this group lost at least 5% body weight; 93% lost at least 10%

Conservative Weight Loss (4 mg/week)

Even at 4 mg, Retatrutide produced 17.1% mean weight loss at 48 weeks — which exceeds the ~15% reported for Semaglutide 2.4 mg in the STEP 1 trial at 68 weeks. The lowest dose with meaningful triple agonist effect.

Target dose: 4 mg subcutaneously once weekly
Titration: 2 mg → 4 mg over 4 weeks
Duration: 48+ weeks
Notes: Fewest side effects of the effective dose groups; 93% achieved ≥5% weight loss

Choosing your target dose: The 8 mg and 12 mg groups produced similar results (22.8% vs 24.2%), but the 12 mg group had higher rates of GI side effects. Starting at 8 mg and evaluating for 8–12 weeks before considering escalation to 12 mg is a reasonable strategy. Even 4 mg produced results that surpass most existing FDA-approved obesity treatments.

Retatrutide Injection Guide

Subcutaneous (SubQ) Injection — Step by Step

Wash Hands

Wash hands thoroughly with soap and water. Prepare a clean workspace with your syringe, alcohol swab, and reconstituted Retatrutide vial.

Swab the Vial Stopper

Wipe the rubber stopper of the Retatrutide vial with an alcohol swab. Let it air-dry for 10–15 seconds.

Draw Your Dose

Pull back the plunger to draw air equal to your dose volume. Insert the needle into the vial, push in the air, invert the vial, and slowly draw out your calculated dose. Tap out any air bubbles. For doses exceeding 100 units, use a larger syringe or split into two draws.

Choose the Injection Site

Retatrutide is injected subcutaneously. Preferred sites: lower abdomen (2–3 inches from the navel), upper thigh (front or outer), or back of the upper arm. Rotate injection sites each week.

Clean the Injection Site

Swab the chosen injection site with a fresh alcohol pad. Allow to air-dry completely before injecting.

Inject

Pinch a fold of skin between your thumb and forefinger. Insert the needle at a 45-degree angle into the pinched skin fold. Push the plunger slowly and steadily. Withdraw the needle and apply light pressure with the alcohol swab if needed.

Dispose Safely

Place the used syringe immediately into a sharps container. Never recap or reuse needles.

Injection Timing & Frequency

Frequency: Once weekly, on the same day each week
Time of day: Any time; morning or evening is fine. Consistency matters more than the specific time
Half-life: Approximately 6 days, supporting the once-weekly schedule
If switching injection days: Maintain at least 3 days between doses when transitioning to a new day of the week
Missed dose: If you miss your scheduled injection by 1–2 days, inject as soon as possible and resume your normal schedule. If more than 3 days late, skip the missed dose and resume on your next scheduled day

Site rotation: Rotate injection sites each week to prevent lipodystrophy (changes in fat tissue at the injection site). Use a different spot within your preferred area — for example, alternate between left and right sides of the abdomen.

Retatrutide Treatment Duration

The Phase 2 trial ran for 48 weeks. Importantly, weight loss had not fully plateaued at the 48-week mark in the higher dose groups, suggesting that continued treatment may produce additional weight loss.

Phase	Weeks	Description
Titration	Weeks 1–12	Gradual dose escalation from 2 mg to target dose; primary focus on GI tolerability; early weight loss begins
Active Weight Loss	Weeks 12–48	Full therapeutic dose; steady, significant weight reduction; most weight loss occurs during this phase
Maintenance	Week 48+	Weight stabilization or continued gradual loss; long-term data not yet available; discontinuation likely leads to weight regain (as seen with all GLP-1 agonists)

Weight regain on discontinuation: Based on extensive data from Semaglutide and Tirzepatide studies, discontinuing GLP-1-based treatments typically results in significant weight regain. It is reasonable to assume Retatrutide will follow the same pattern. Plan for long-term use if weight maintenance is the goal. The optimal maintenance dose and strategy for Retatrutide have not been established.

Stacking & Contraindicated Combinations

Critical warning: Do NOT combine Retatrutide with any other GLP-1 receptor agonist. Retatrutide already has full GLP-1 agonism built in. Adding another GLP-1 agonist creates redundant receptor activation with severely increased risk of adverse effects.

Contraindicated Combinations (DO NOT USE)

Compound	Class	Why Not
Semaglutide	GLP-1 agonist	Redundant GLP-1 receptor activation; severe GI side effects; hypoglycemia risk
Liraglutide	GLP-1 agonist	Same mechanism overlap; no additive benefit, only added risk
Tirzepatide	GLP-1/GIP dual agonist	Redundant on both GLP-1 and GIP receptors; dangerous overlap

Speculative Combinations (Community Discussion — No Clinical Data)

The following combinations are discussed in community forums but have NO clinical evidence supporting their use with Retatrutide. They are included for informational purposes only.

Compound	Rationale	Caution
Ipamorelin / CJC-1295	GH secretagogues for muscle preservation during rapid weight loss	No interaction data with Retatrutide; GH elevation may affect glucose homeostasis; speculative
BPC-157	GI healing support for those experiencing significant GI side effects	No interaction data; BPC-157 interacts with the NO system; purely speculative use

No stacking data exists. Because Retatrutide is an investigational compound with limited human data, there are NO studies evaluating its combination with any other peptide or drug. Any combination use is entirely at your own risk. The safest approach is to use Retatrutide as a standalone treatment.

Explore peptide combinations in our Peptide Stack Builder or browse the Top 10 Peptide Stacks guide.

Safety, Side Effects & Contraindications

Investigational Compound: Retatrutide is NOT FDA-approved. Safety data is limited to a single Phase 2 trial with 338 participants over 48 weeks. Long-term safety, rare adverse events, and effects in diverse populations are unknown. You are assuming risk that has not been fully characterized. Phase 3 trials are ongoing.

Gastrointestinal Side Effects (Most Common)

GI side effects are dose-dependent — they are more frequent at higher doses and during the titration period. Most improve over time as the body acclimates.

Side Effect	Frequency (12 mg group)	Notes
Nausea	Up to 45%	Most common; peaks during titration, improves over time
Diarrhea	Up to 27%	More common at higher doses; usually mild to moderate
Vomiting	Up to 22%	More likely if titration is skipped or rushed; reduce dose if persistent
Constipation	Reported	Less common than nausea and diarrhea; increase fiber and water intake
Decreased appetite	Common	Expected pharmacological effect; ensure adequate nutrition despite reduced hunger

Glucagon Receptor-Specific Concerns

The glucagon receptor component distinguishes Retatrutide from other GLP-1-based treatments and introduces unique considerations:

Blood glucose monitoring: Glucagon promotes hepatic glucose production, which may partially counteract the glucose-lowering effects of GLP-1 and GIP. The net effect in the Phase 2 trial was improved glycemic control, but individual responses may vary. Regular blood glucose monitoring is strongly recommended, especially for diabetics and pre-diabetics.
Hepatic effects: Glucagon stimulates hepatic fat oxidation — a therapeutic benefit for fatty liver. However, baseline and periodic liver function tests (ALT, AST) are recommended to monitor hepatic effects.
Heart rate: GLP-1 agonists are associated with small increases in resting heart rate. The addition of glucagon receptor agonism could theoretically amplify this. Monitor resting heart rate, especially in the first weeks of treatment.

Expected Contraindications (Based on GLP-1 Agonist Class)

Because Retatrutide does not have an approved drug label, formal contraindications have not been established. However, based on the GLP-1 agonist class and the Phase 2 trial exclusion criteria, the following are expected contraindications:

Personal or family history of medullary thyroid carcinoma (MTC) — GLP-1 agonists carry a class-wide boxed warning for thyroid C-cell tumors in rodent studies
Multiple endocrine neoplasia syndrome type 2 (MEN2)
History of pancreatitis — GLP-1 agonists have been associated with increased pancreatitis risk
Pregnancy and breastfeeding — no safety data; avoid use entirely
Type 1 diabetes — Retatrutide has not been studied in T1D; glucagon receptor agonism could worsen glycemic control
Severe hepatic impairment — the glucagon component directly affects hepatic metabolism; use in liver disease has not been studied
Severe renal impairment — insufficient data on use in advanced kidney disease

Recommended Baseline Labs

Before starting Retatrutide, obtain the following baseline bloodwork to enable ongoing monitoring:

Fasting glucose and HbA1c
Complete metabolic panel (CMP) including liver function (ALT, AST)
Lipid panel (total cholesterol, LDL, HDL, triglycerides)
Thyroid panel (TSH, free T4)
Kidney function (BUN, creatinine, eGFR)
Lipase and amylase (pancreatic markers)
Resting heart rate and blood pressure

FDA approval timeline: Retatrutide is currently in Phase 3 clinical trials under Eli Lilly's TRIUMPH program. FDA approval is not expected before late 2026 at the earliest, with 2027 being more realistic. Until approved, there is no FDA-regulated commercial product, no standardized dosing label, and no post-marketing safety surveillance. Any use prior to approval is inherently investigational.

Common Retatrutide Dosing Mistakes

Avoid these critical errors when using Retatrutide:

Starting at the full target dose without titrating: Skipping the 4-week titration at 2 mg dramatically increases the risk of severe nausea, vomiting, and diarrhea. The Phase 2 trial used a mandatory step-up protocol for good reason. Start low and titrate up over 12 weeks.

Treating Retatrutide dosing the same as Semaglutide: Retatrutide is a triple agonist with glucagon receptor activity — a fundamentally different pharmacological profile. Dosing schedules, titration timelines, side effects, and monitoring requirements differ. Do not assume protocols are interchangeable.

Combining with another GLP-1 agonist (Semaglutide, Liraglutide, Tirzepatide): Retatrutide already has full GLP-1 receptor agonism built in. Stacking with another GLP-1 agonist creates dangerous redundancy with drastically increased GI side effects and hypoglycemia risk. There is zero clinical data supporting this.

Not monitoring blood glucose: The glucagon receptor component adds complexity to blood sugar regulation. Unlike pure GLP-1 agonists, the interplay between insulin-promoting (GLP-1/GIP) and glucose-raising (glucagon) effects requires careful monitoring, especially in diabetics and pre-diabetics.

Expecting FDA-level safety data from a Phase 2 compound: Retatrutide has been studied in only one major Phase 2 trial with 338 participants over 48 weeks. Long-term safety, rare adverse events, and effects in diverse populations are unknown. Phase 3 data is still being collected. Understand you are using an investigational drug with limited safety data.

Ignoring reconstitution math at high doses: At 12 mg per dose with a 10 mg/mL concentration, you need 1.2 mL (120 units) — which exceeds the capacity of a standard 1 mL insulin syringe. You must either split the dose into two injections or use a higher concentration. Miscalculating this leads to under-dosing.

Not getting baseline labs before starting: Given Retatrutide’s triple receptor activity, baseline bloodwork is essential: fasting glucose, HbA1c, lipid panel, liver function tests, thyroid panel, and kidney function. Without baseline data, you cannot track changes or catch emerging problems.

Frequently Asked Questions

Key Takeaways

Retatrutide is the first triple receptor agonist (GLP-1 + GIP + Glucagon) — the glucagon receptor component drives additional energy expenditure and hepatic fat oxidation beyond what dual agonists achieve
Phase 2 results: up to 24.2% body weight loss at 48 weeks (12 mg group) — the largest ever reported for an obesity drug
Titration is mandatory: 2 mg → 4 mg → 8 mg → 12 mg over 12 weeks. Never skip the step-up protocol
Once-weekly subcutaneous injection — same day each week, any time of day, with an approximately 6-day half-life
Do NOT combine with other GLP-1 agonists (Semaglutide, Liraglutide, Tirzepatide) — Retatrutide already has full GLP-1 agonism
GI side effects are dose-dependent — nausea, diarrhea, and vomiting are common, especially during titration, but generally improve
Blood glucose monitoring is critical — the glucagon receptor component adds complexity to glycemic regulation
Baseline labs are essential — fasting glucose, HbA1c, liver function, lipids, thyroid, kidney function, and pancreatic markers before starting
NOT FDA-approved — currently in Phase 3 trials (TRIUMPH program). Approval expected no earlier than late 2026–2027
Available only through compounding pharmacies or research suppliers — no branded product exists. Quality and purity vary. Manual reconstitution and dose calculation required

This article is for educational and informational purposes only. See our Disclaimer.

References

Jastreboff AM, et al. “Triple-hormone-receptor agonist retatrutide for obesity — a Phase 2 trial.” N Engl J Med. 2023;389(6):514-526. PubMed
Rosenstock J, et al. “Retatrutide, a GIP, GLP-1 and glucagon receptor agonist, for people with type 2 diabetes: a randomised, double-blind, placebo and active-comparator-controlled, parallel-group, Phase 2 trial conducted in the USA.” Lancet. 2023;402(10401):529-544. PubMed
Nauck MA, et al. “GLP-1 receptor agonists in the treatment of type 2 diabetes — state-of-the-art.” Mol Metab. 2021;46:101102. PubMed
Finan B, et al. “A rationally designed monomeric peptide triagonist corrects obesity and diabetes in rodents.” Nat Med. 2015;21(1):27-36. PubMed
ClinicalTrials.gov. “TRIUMPH 1: A Study of Retatrutide (LY3437943) in Participants With Obesity or Overweight.” NCT05929066.
ClinicalTrials.gov. “TRIUMPH 2: A Study of Retatrutide (LY3437943) in Participants With Obesity.” NCT05929079.

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