Information only. Not medical advice. Retatrutide is not an approved medicine in the UK.
Retatrutide Guide UK

Retatrutide Dosing in Trials (Research Reference)

Last updated 13 June 2026

Quick answer

In trials, retatrutide was given once a week. Doses were raised slowly over several weeks, up to about 12 mg per week at the top end. This page is a research reference only. It is not dosing advice, and retatrutide is not approved for people to take.
Important: This page describes what trials used. It is not a guide for using retatrutide. It is not an approved medicine. See our disclaimer.

How trials built up the dose

Trials did not start at the top dose. They began low and stepped up every few weeks. This slow build is called titration. It gave the body time to adjust and cut down on nausea.

Why the "start low, go slow" pattern

Most side effects in trials were stomach-related and showed up more when the dose rose fast. A gentle build lined up with fewer problems. This links to retatrutide's long half-life, which means levels take time to settle.

Why doses are measured carefully

Researchers measure peptides in milligrams (mg) and micrograms (mcg). Mixing the powder with the right amount of water sets the strength. Our calculatorshows how concentration and syringe units are worked out for research.

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Common questions

What doses were used in retatrutide trials?+

Trials tested a range of weekly doses, commonly up to about 12 mg per week at the top end, reached slowly over several weeks. This is research information, not a guide for taking anything.

Why are doses raised slowly?+

Raising the dose in small steps gave fewer stomach side effects in trials. A slow build let the body adjust.

Sources