- Volume (mL) = amount (mg) ÷ concentration (mg/mL).
- Syringe units (U-100) = volume × 100.
Check it against your label
- Where the product came from, and what the container says about its contents and strength.
- The concentration, written down when it was mixed.
- Any guidance from a clinician who knows you.
Frequently asked questions
In short
- The sum is volume = amount ÷ concentration, then × 100 for U-100 units.
- With no approved label, nothing on this page can tell you whether an amount is sensible.
- Be sure of your source and the written concentration before any number goes into a calculator.
- Reko shows a plain regulatory status for each compound it lists.
Is there a label I can check?
No. Retatrutide has no approved label. Lilly announced in July 2026 that it plans to file for approval in early 2027, and a filing is not an approval.
Why is the status shown in Reko?
Because knowing whether a regulator has approved something is part of understanding what you are recording.
Does the tool give a dose?
No.
What does this tool do?
This tool converts an amount in milligrams and a concentration into millilitres and syringe units. It is the same arithmetic as for any vial. It says nothing about what an amount should be.
On 2 November 2026 retatrutide is in phase 3 trials and is not approved by the FDA. We also found no EU authorisation for it on the European Medicines Agency's site. There is no prescribing information to check your numbers against.
More on the arithmetic
If the concentration is written as an amount in a volume, such as 10 mg in 2 mL, divide first: 10 ÷ 2 = 5 mg/mL.
A worked example
Example. These numbers are made up to show the steps. They are not a label value and not a suggestion.
A made-up amount of 2 mg from a mix of 5 mg/mL.
- 2 ÷ 5 = 0.4 mL.
- 0.4 × 100 = 40 units.
Related pages
Medical disclaimer. This page is for information only and is not medical advice. Talk to your prescriber before changing how you take your medicine. Reko does not suggest doses and takes no responsibility for dosing errors.
How Reko does this in the app
Reko lets you track a compound with its own unit and shows a plain regulatory status next to it. Its estimated level uses published absorption and elimination half-lives and is an estimate, not a blood test. Retatrutide is on Reko's compound list, marked as in trials and not approved.
Reko records what you and your prescriber decide. It never suggests a dose, and this page is not medical advice.
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