Retatrutide: uses, evidence, cost and safety
Retatrutide is an investigational triple agonist targeting the GIP, GLP-1 and glucagon receptors. It is NOT FDA-approved and is not legally available for prescription or compounding; it exists only within clinical trials. Early phase 2 data reported large average weight reductions, but phase 3 safety and efficacy results are still needed.
What Retatrutide is
Retatrutide is a triple gip / glp-1 / glucagon receptor agonist (investigational). It is marketed as None — investigational. Retatrutide is an investigational triple agonist targeting the GIP, GLP-1 and glucagon receptors. It is NOT FDA-approved and is not legally available for prescription or compounding; it exists only within clinical trials. Early phase 2 data reported large average weight reductions, but phase 3 safety and efficacy results are still needed.
Regulatory status
INVESTIGATIONAL. Not FDA-approved. Available only through clinical trials.
How it works
Adds glucagon-receptor agonism to the dual-incretin mechanism, which may increase energy expenditure in addition to reducing appetite.
Clinical evidence
Mean percent body-weight change from controlled trials. Bars show trial averages over the study period; individual results vary widely and are not guaranteed. Values shown are percentage points.
Phase 2 data published in 2023 reported mean weight reductions above 20% at higher doses over 48 weeks. These are early-stage results; phase 3 trials are ongoing.
| Trial | Arm | Result | Duration | Comparator | Source |
|---|---|---|---|---|---|
| SURMOUNT-1 | Tirzepatide 15 mg | −20.9% | 72 weeks | Placebo −3.1% | NEJM 2022 (Jastreboff et al.) |
| SURMOUNT-1 | Tirzepatide 10 mg | −19.5% | 72 weeks | NEJM 2022 | |
| SURMOUNT-1 | Tirzepatide 5 mg | −15.0% | 72 weeks | NEJM 2022 | |
| SURMOUNT-5 | Tirzepatide (max tolerated) | −20.2% | 72 weeks | vs semaglutide −13.7% | NEJM 2025 (Aronne et al.) |
| STEP 1 | Semaglutide 2.4 mg | −14.9% | 68 weeks | Placebo −2.4% | NEJM 2021 (Wilding et al.) |
| STEP 8 | Semaglutide 2.4 mg | −15.8% | 68 weeks | vs liraglutide 3.0 mg −6.4% | JAMA 2022 (Rubino et al.) |
| SCALE | Liraglutide 3.0 mg | −8.0% | 56 weeks | Placebo −2.6% | NEJM 2015 |
| SELECT | Semaglutide 2.4 mg | 20% MACE reduction | ~40 months | Cardiovascular outcomes | NEJM 2023 |
Dosing and titration
See the FDA label for the approved dose schedule.
Common and serious side effects
Reported gastrointestinal effects consistent with the incretin class in phase 2; the full safety profile is not established.
Warnings and contraindications
Because retatrutide is investigational, any product sold to consumers as 'retatrutide' outside a trial is unapproved and unregulated. We do not evaluate or link to such sellers.
Monitoring and laboratory work
A legitimate programme does not simply ship medication. Before starting a GLP-1, a clinician should establish a baseline — typically weight and BMI, blood pressure, and laboratory work including HbA1c or fasting glucose, a lipid panel, and renal and hepatic function. A personal or family history of medullary thyroid carcinoma or Multiple Endocrine Neoplasia type 2 is a contraindication, and a history of pancreatitis, gallbladder disease, severe gastrointestinal disease or diabetic retinopathy changes the risk calculus and should be discussed.
During treatment, tolerance should be reviewed at each dose escalation rather than automatically. Persistent vomiting, severe abdominal pain radiating to the back, or signs of gallbladder disease warrant prompt clinical contact rather than a message to a chat widget.
Questions to ask your clinician
- Given my history, is a GLP-1 appropriate for me at all — and is there a reason it might not be?
- What baseline laboratory work will you order before I start?
- What is the target dose, and how quickly will we escalate to it?
- What side effects should make me call you rather than wait?
- What is the plan for maintenance, and what happens if I stop?
- Will I see the same clinician at follow-up, or a different one each time?
Questions to ask about the pharmacy
The pharmacy matters more than the telehealth brand on the front of the website. The telehealth company arranges the consultation; the pharmacy makes the medicine you inject.
- Which specific pharmacy will fill my prescription? Not "our network" — the name of the facility.
- Is it a 503A state-licensed pharmacy or a 503B FDA-registered outsourcing facility? These are different regulatory categories with different oversight, and a company can use both for different products.
- In which state is it licensed, and can I look up the licence? State boards of pharmacy publish licensee databases.
- What is the exact salt form and concentration? Semaglutide sodium and semaglutide acetate are not the same active ingredient as the semaglutide base in approved products, and the FDA has said they are not appropriate for compounding.
- Is the vial single-dose or multi-dose? A multi-dose vial requires you to measure each dose yourself, which is the most common source of the dosing errors behind reported adverse events.
- Will you provide a certificate of analysis?
- Has the pharmacy received any FDA warning letter or state board action?
A provider that answers all seven in writing is demonstrating something real. A provider that will not name its pharmacy has given you an answer, whether it intended to or not.
What happens when you stop
This is the question the marketing rarely addresses, and it belongs in any honest discussion of cost. In the published extension data, a substantial proportion of lost weight returns after discontinuation — the STEP 1 extension found participants regained roughly two-thirds of the weight they had lost within a year of stopping.
The practical implication is financial as well as clinical. If maintaining the result requires continuing the medication, then the number that matters is not the monthly price but the indefinite monthly price. A programme that is $186 a month is $2,232 a year, and potentially the same again the year after. Anyone comparing providers on a first-month promotion is optimising the wrong variable.
Storage and handling
Compounded GLP-1 preparations are generally refrigerated, and specific storage requirements vary by pharmacy and formulation — this is one reason a provider that will not tell you which pharmacy compounds your medication is withholding something you need. Ask for the beyond-use date, which for a compounded preparation is not the same as a manufacturer's expiry date and is typically much shorter. Never use a preparation that has changed colour, become cloudy, or contains particulates.
How to verify any of this yourself
You should not take our word for a price, and you do not have to. Every figure here can be checked in a few minutes.
- Go to the provider's own pricing page. Not a comparison site — the provider's. Comparison sites in this category routinely publish contradictory numbers for the same programme in the same month.
- Find the ongoing price, not the headline. Look for the words "first month", "intro", "starting at" or "new patients". If they appear, the number beside them is not what you will pay in month two.
- Add the membership. If the medication and the membership are billed separately, add them. That sum is your real monthly cost.
- Ask what the highest dose costs. By email or chat, so you have it in writing.
- Ask about early cancellation before you commit to a plan longer than a month.
- Check the manufacturer. For any brand-name drug, price it at LillyDirect or NovoCare before you buy it through a telehealth platform. Some platforms resell brand drugs at four to eleven times the manufacturer's own direct price.
If a provider will not answer questions 4 or 5 in writing, that is itself information.
Who is actually who: the entities in this transaction
The single biggest source of confusion in telehealth medicine is that people assume one company is doing all of it. Usually four or five separate entities are involved, with different regulators and different duties to you.
| Entity | What it is | Regulated by | What it is NOT |
|---|---|---|---|
| Telehealth company | The website you sign up on. Arranges the consultation, handles billing and logistics. | State corporate practice rules; FTC for advertising | Not a pharmacy. Does not make your medicine. |
| Prescribing clinician | The licensed physician, NP or PA who evaluates you and writes the prescription. | Their state medical or nursing board | Not employed by the pharmacy. Must exercise independent judgement. |
| 503A compounding pharmacy | A state-licensed pharmacy compounding for an individual patient against a specific prescription. | State board of pharmacy; FDA for some provisions | Not FDA-approved. Products are not reviewed before marketing. |
| 503B outsourcing facility | An FDA-registered facility that may compound in bulk without patient-specific prescriptions. | FDA, including cGMP inspection | Still not making FDA-approved products. |
| Manufacturer | Eli Lilly, Novo Nordisk. Makes the FDA-approved branded drug. | FDA — full premarket approval | Not involved in compounded products at all. |
Equally: a provider's statement about which pharmacy it uses is a provider-reported relationship until someone verifies it. We label it that way, and so should you when you read it.
Eligibility, and who is likely to be declined
A licensed clinician decides whether treatment is appropriate. No website can promise you eligibility, and one that implies it should worry you.
Typical criteria for GLP-1 weight management follow the approved labels: a BMI of 30 or above, or 27 or above with at least one weight-related condition such as hypertension, dyslipidaemia, obstructive sleep apnoea or type 2 diabetes. Absolute contraindications include a personal or family history of medullary thyroid carcinoma or Multiple Endocrine Neoplasia type 2, and pregnancy. A history of pancreatitis, gallbladder disease, severe gastrointestinal disease, or diabetic retinopathy changes the risk calculation and must be disclosed.
Be honest on the intake form. The temptation to shade an answer to secure a prescription is understandable and it is a bad trade: the questions exist because the contraindications are real.
State availability, and why it varies
Availability is not uniform across the United States, and the reasons are structural rather than arbitrary. Clinicians must be licensed in your state, not merely somewhere. Pharmacies must hold a non-resident licence to ship into your state. Some states impose additional telehealth requirements — a synchronous video visit rather than an asynchronous questionnaire, for instance — and some restrict compounded products more tightly than others.
The practical consequence is that a provider genuinely available in Texas may not serve California or North Carolina, and pricing sometimes differs by state as well. Confirm availability for your state before you compare anything else, because a cheaper provider that cannot ship to you is not cheaper.
Limitations of this analysis
Every page on this site should tell you where it stops being reliable. This one stops here.
Prices decay quickly. This is the fastest-moving data we publish. Brand programmes have changed twice in the last eight months; compounded providers change plan structures without notice. Treat any figure more than about thirty days past its verification date as indicative, and confirm at checkout.
Competitor pricing is reported, not captured by us. We hold dated captures for brand pricing and for NexLife. All provider pricing is captured from each provider's own published pages and dated, and carries a Verified label. Pharmacy licences are the exception: we have not independently verified them for any provider, and they carry a Reported — pending verification label. We publish that distinction rather than flattening it, because comparison sites in this category contradict each other routinely — and a figure repeated by three affiliate blogs is still one unverified figure.
We have not audited pharmacy licences. Where a provider names its compounding pharmacies, we report that as a provider-disclosed relationship. We have not independently verified each facility's licence or registration, and we say so rather than implying an audit we did not perform.
Advertised availability is not your availability. Eligibility is decided by a licensed clinician, and state-by-state access varies with clinician licensure and pharmacy shipping permissions. No page can promise you a price you will actually be offered.
We are commercially funded. The publisher and certain principals have financial relationships with some of the providers listed here, and we may earn a commission from provider links. That is disclosed in the footer of every page. It does not change a score, a rank or a conclusion — but you should read anything written by anyone with a commercial interest, including us, with that in mind, and check the arithmetic we publish rather than taking our word for the result.
Frequently asked questions
Is Retatrutide FDA-approved?
INVESTIGATIONAL. Not FDA-approved. Available only through clinical trials.
How does Retatrutide work?
Adds glucagon-receptor agonism to the dual-incretin mechanism, which may increase energy expenditure in addition to reducing appetite.
What are the most common side effects of Retatrutide?
Reported gastrointestinal effects consistent with the incretin class in phase 2; the full safety profile is not established.
Who should not take Retatrutide?
Because retatrutide is investigational, any product sold to consumers as 'retatrutide' outside a trial is unapproved and unregulated. We do not evaluate or link to such sellers.
Sources
- U.S. Food and Drug Administration — prescribing information and drug labels for None — investigational.
- Pivotal randomized controlled trials as cited in the evidence section (SURMOUNT, SURPASS, STEP, SUSTAIN, SCALE as applicable).
- CMS National Plan & Provider Enumeration System — clinician verification for reviewed providers.
- ClinicalTrials.gov — trial registrations for investigational agents.
The trial record
| Trial | Design | n | Dose | Duration | Primary result | Citation |
|---|---|---|---|---|---|---|
| SURMOUNT-1 | Phase 3, randomised, double-blind, placebo-controlled | 2,539 | 5 / 10 / 15 mg SC weekly | 72 wks | −15.0% / −19.5% / −20.9% vs −3.1% placebo | Jastreboff, NEJM 2022; NCT04184622 |
| SURMOUNT-2 | Phase 3, RCT, in type 2 diabetes | 938 | 10 / 15 mg SC weekly | 72 wks | −12.8% / −14.7% vs −3.2% placebo | Garvey, Lancet 2023; NCT04657003 |
| SURMOUNT-3 | Phase 3, RCT, after 12-wk intensive lifestyle lead-in | 806 | Max tolerated (10/15 mg) | 72 wks | −18.4% additional, vs +2.5% placebo | Wadden, Nat Med 2023; NCT04657016 |
| SURMOUNT-4 | Randomised WITHDRAWAL after 36-wk open-label lead-in | 670 | Max tolerated | 88 wks | Continue: −5.5% further. Withdraw to placebo: +14.0% REGAINED | Aronne, JAMA 2024; NCT04660643 |
| SURMOUNT-5 | Phase 3b, OPEN-LABEL, active-controlled head-to-head | 751 | Max tolerated vs semaglutide | 72 wks | −20.2% vs semaglutide −13.7%, p<0.001 | Aronne, NEJM 2025; NCT05822830 |
| SURPASS-2 | Phase 3, RCT, type 2 diabetes, active-controlled | 1,879 | 5 / 10 / 15 mg vs semaglutide 1 mg | 40 wks | HbA1c −2.01 to −2.30% vs −1.86% | Frías, NEJM 2021; NCT03987919 |
| SURPASS-CVOT | Phase 3, cardiovascular outcomes, vs dulaglutide | 13,299 | Max tolerated | ~4.5 yrs | Non-inferior for MACE; not superiority vs placebo | Nicholls, 2024; NCT04255433 |
1. They are means, not promises. A −20.9% mean in SURMOUNT-1 contains people who lost far more and people who lost almost nothing. A trial average tells you what happened to a population; it does not tell you what will happen to you.
2. Every one is an FDA-APPROVED SUBCUTANEOUS INJECTION. No trial in this table tested a compounded preparation, a microdose regimen, or an orally disintegrating tablet. When these figures appear on a page selling a compounded ODT, evidence has been moved across a dosage form without justification.
3. All were funded by Eli Lilly, which manufactures tirzepatide. That is normal in drug development and does not make the results false — these are large, peer-reviewed studies. It belongs in the citation anyway, and it matters most in SURMOUNT-5, where the funder made the winning drug and the trial was open-label.
Jastreboff AM et al., N Engl J Med 2022, n=2,539 (NCT04184622). The effect rises with dose — which is precisely why a ~1mg 'microdose' cannot be expected to produce the headline result. FDA-approved subcutaneous injection.
The evidence is strong exactly where it was gathered and silent everywhere else. The gap between those two things is where most of the marketing in this industry operates, and recognising it is the single most useful skill a patient in this market can have.
Dosing, titration, and what it does to your bill
| Period | Dose | What it is for |
|---|---|---|
| Weeks 1–4 | 2.5 mg | Tolerance-building only. This dose is not intended to produce weight loss. If your provider's price is quoted at 2.5 mg, that is not the price of treatment. |
| Weeks 5–8 | 5 mg | First therapeutic dose (−15.0% in SURMOUNT-1). |
| Weeks 9–12 | 7.5 mg | Escalate only if tolerated. |
| Weeks 13–16 | 10 mg | A common maintenance dose (−19.5%). |
| Weeks 17–20 | 12.5 mg | Escalate only if tolerated. |
| Week 21+ | 15 mg | Maximum maintenance dose (−20.9%). |
The advertised price is usually the 2.5 mg price. On a programme that escalates with dose, the rate you are quoted at signup is for a dose the label explicitly describes as a starting dose — not a treatment dose. Ask what you will pay at 10 mg, and compare that number instead.
A 'microdose' of ~1 mg/week sits below every dose in SURMOUNT. The trials used 5, 10 and 15 mg. A microdose is not a discounted route to the SURMOUNT result; it is a different product with a smaller expected effect and no equivalent trial evidence.
Safety, contraindications and monitoring
Tirzepatide carries a boxed warning for thyroid C-cell tumours, based on rodent data. It is contraindicated in anyone with a personal or family history of medullary thyroid carcinoma or Multiple Endocrine Neoplasia syndrome type 2. This is not a precaution to weigh; it is a hard stop.
Serious but less common risks include pancreatitis, gallbladder disease (cholelithiasis and cholecystitis), acute kidney injury secondary to dehydration from vomiting or diarrhoea, diabetic retinopathy complications in people with existing retinopathy, and hypoglycaemia when combined with insulin or a sulfonylurea. Severe abdominal pain radiating to the back warrants urgent assessment for pancreatitis, not a message to a chat widget.
Before starting, a clinician should establish a baseline: weight and BMI, blood pressure, HbA1c or fasting glucose, a lipid panel, and renal and hepatic function. During treatment, tolerance should be reviewed at each escalation step rather than escalated automatically on a calendar.
Percentage of participants reporting each event. Gastrointestinal effects dominate, are usually mild-to-moderate, and are most pronounced during dose escalation. Source: SURMOUNT-1, N Engl J Med 2022.
Discontinuation: what the withdrawal trial found
Aronne LJ et al., JAMA 2024, n=670 (NCT04660643). After a 36-week open-label lead-in, participants randomised to placebo regained ~14% of body weight over the following 52 weeks; those who continued lost a further ~5%. This is the single most important trial for understanding the true cost of treatment.
In SURMOUNT-4 — the randomised withdrawal trial — participants taken off tirzepatide after a 36-week lead-in regained roughly 14% of body weight over the following year, while those who continued lost a further ~5%. This is the trial that most changes the arithmetic of treatment, and it is almost never cited on a pricing page.
The consequence is financial as much as clinical. If holding the result requires holding the medication, then the figure that matters is not the introductory price, and not even the annual price. It is the indefinite monthly price. Anyone selecting a provider on the strength of a first-month rate is optimising the wrong variable entirely.
Questions to ask your clinician
- Given my history — specifically thyroid, pancreatic and gallbladder — is a GLP-1 appropriate for me at all?
- What baseline laboratory work will you order before I start?
- What is my target dose, and how quickly will we escalate?
- Which side effects should make me call you rather than wait it out?
- What is the plan for maintenance, and what happens if I stop?
- Will I see the same clinician at each follow-up, or a different one each time?
Compounded, brand, microdose, ODT — four different products
These words are used interchangeably in marketing and they are not interchangeable at all. The distinction decides what evidence applies to what you are actually buying.
| Product | Regulatory status | Trial evidence |
|---|---|---|
| Brand Zepbound / Mounjaro (injection) | FDA-approved. Reviewed for safety, effectiveness and quality before marketing. | Direct. SURMOUNT and SURPASS tested exactly this product. |
| Brand Foundayo (oral, orforglipron) | FDA-approved. Its own trial programme. | Direct, for that product. |
| Compounded tirzepatide (injection, full dose) | NOT FDA-approved. No premarket review of safety, effectiveness or quality. | None for the compounded product itself. Same molecule, same route — but the product in your hand was never in a trial. |
| Microdose (~1 mg/wk) | NOT FDA-approved. | None. Sits BELOW every dose in SURMOUNT (5/10/15 mg). Expect a smaller effect. |
| ODT / oral compounded | NOT FDA-approved. | NONE. No trial has ever tested it. Oral bioavailability for these peptides is a real pharmacological problem and is unpublished for this product. |
The evidence is strong exactly where it was gathered and silent everywhere else. The gap between those two things is where most of the marketing in this industry operates, and recognising it is the single most useful skill a patient in this market can have.