Only the studies used these amounts
Retatrutide dosage: study amounts aren't a use plan
Eli Lilly tested set amounts in Phase 1b, an early safety study, and Phase 2. Retatrutide isn't approved, and the plans don't direct your care.
Study amounts don't make an approved retatrutide dose
Eli Lilly made retatrutide for tests under medical care. Phase 2 results led to more study, not a dose doctors can prescribe.
The FDA still hasn't approved retatrutide. There isn't an official dose for patients.
This page tells you what study teams gave. It isn't a plan for your care.
Each amount and study length comes from a published paper. The numbers belong to those studies and those people.
Higher amounts brought more side effects. Nausea and faster pulses needed close watching.
Study doctors could pause, lower, or stop the drug. An online vial doesn't come with that care.
Research-labeled material may be false, too strong, or dirty. Copying a study amount can't fix those risks.
Keep the study numbers in their proper place. They aren't directions for you or your doctor.
Retatrutide dosage in the first early safety study
A 2022 Phase 1b study, an early safety test, enrolled 72 adults with type 2 diabetes [4]. Staff used these amounts:
- 0.5 mg once each week.
- 1.5 mg once each week.
- 3 mg once each week.
- 3/6 mg meant 3 mg in weeks 1–4, then 6 mg.
- 3/6/9/12 mg meant 3, 6, 9, then 12 mg.
Staff gave each shot beneath the skin. They watched each group for 12 weeks.
The drug had a half-life near 6 days [4]. That slow fall supported weekly shots in later studies.
This list isn't your dose plan. Retatrutide half life explains the time measure.
The list only shows what staff tested. It can't set your dose or make the drug safe for you.
Retatrutide dosage rose in steps during Phase 2
In the obesity Phase 2 study, staff used 1 mg, 4 mg, 8 mg, or 12 mg [1]. They gave weekly shots into fatty tissue. The test lasted 48 weeks.
People assigned a larger final amount started on a smaller one. The Phase 1b early safety study had tested that step-by-step plan first.
For type 2 diabetes, the Phase 2 study used 0.5–12 mg [2]. The team made each increase in a set order. The study lasted 36 weeks.
Higher amounts caused more nausea and bowel trouble. The study staff could delay the next step or stop the drug.
The fatty-liver Phase 2 study used 1, 4, 8, or 12 mg [5]. Weekly shots continued for 48 weeks. The main liver check came at week 24.
A 2026 review found that the three-month blood-sugar test improved [15]. Faster increases also brought more stomach trouble.
Every published plan spread increases across weeks. The staff watched how each person felt. They could pause, lower, or stop the drug.
Those findings shaped Phase 3 study plans. An online product doesn't give you that care.
The numbers describe research, not directions for you. Your own doctor can explain care that is already approved for you.
Retatrutide cannot be prescribed or compounded for routine care
There is no approved formulation of retatrutide. There is no manufacturer-specified reconstitution protocol, storage standard, or concentration specification for any consumer or research product.
The trial drugs used in Phase 1/2 were pharmaceutical-grade investigational products prepared to Good Manufacturing Practice (GMP) standards under clinical trial authorization. Gray-market vials are not that product.
How to reconstitute retatrutide — There is no standardized answer to this question because no approved product with a reconstitution standard exists. The published trials used pre-filled pharmaceutical formulations under clinical supervision; no reconstitution protocol was published in the papers.
The question raised by this address is whether a telehealth visit can lead to a retatrutide prescription. Within prescription-only care, Promise Peptides (mypromise.com) prescribes compounded tirzepatide, a different molecule in the same broad drug class. Retatrutide remains investigational; this service does not offer it, and no telehealth service can prescribe it. A clinician licensed in the U.S. assesses the person's request and can refuse to prescribe. Only U.S. patients can use the service, and their options are shaped by the state and the treatment. The compounded tirzepatide product has no FDA approval, while FDA-approved tirzepatide exists. Research-labeled retatrutide vials are still sold online; they are not approved medicines and do not supply a lawful prescription route. An ordinary telehealth visit cannot convert an investigational drug into a medicine a clinician may prescribe.
How to reconstitute retatrutide has no checked answer
No approved retatrutide product exists. That means there's no checked way to mix its powder with water.
Study teams used drug made for their trials. Trained staff gave each shot under medical care.
Online vials lack proof of the drug, strength, and cleanliness. You could be mixing a different substance.
We won't give mixing steps for an unapproved shot. A recipe can't turn an unchecked vial into safe medicine.
Mixing can't prove what powder you received. Your safety depends on knowing the drug, and an online vial leaves that unknown.
Studies used weekly retatrutide shots kept by staff
Study teams gave weekly shots beneath the skin. They used that route in all Phase 1 and Phase 2 work.
No paper has reported a pill or a nasal spray. You can't assume another form would act the same.
A 6-day half-life supported the timing [4]. Blood levels dropped slowly between study shots.
Study staff controlled storage. No checked storage rule exists for online retatrutide. We don't know how long those vials stay sound.
Staff stored a known product under set conditions. Those rules can't make sense of a vial with unknown contents.