Key takeaways
- Reko logs compounded semaglutide, tirzepatide and other vials, and counts down what is left.
- You enter what is printed on your vial. Strengths differ between pharmacies, so a dose in units from one vial may not match another.
- Reko does not judge, recommend or sell any source, and it never suggests a dose.
Why a record matters more with a vial
A branded pen delivers set doses. With a vial, the amount you draw depends on the strength on the label and on your syringe. If a new vial has a different strength, the same number of units can be a different dose. Writing down the milligrams as well as the units keeps that clear.
What Reko keeps for you
- Each vial. The amount in it, the water added if you mixed it, what is left, and how long you have been told to use it.
- Each dose. Amount, time and injection site, attached to the vial it came from.
- The sum. A reconstitution calculator turns the vial and the dose you were prescribed into syringe units, and warns when a draw falls between the markings.
- A new vial. A vial with a different strength stays separate from the old one, so your counts do not mix.
- Everything around it. Weight, side effects, food, water, sleep and labs in the same record.
The estimated level
Reko can draw an estimated level for injected semaglutide or tirzepatide from your logged doses and the half-life published for that medicine. Those figures come from studies of approved products, and nobody has measured your own vial, so treat the curve as a rough picture and never as a blood test.
What to know about compounded medicines
The U.S. Food and Drug Administration says compounded drugs do not go through its approval process, so it does not check their safety, effectiveness or quality before they reach the market. Read Compounding and the FDA: Questions and Answers. Questions about a product, its quality or its legal status are for your prescriber and your pharmacist.
New to the words? See the peptide glossary.
Free tools for vials
Questions people ask
Does Reko tell me how much to draw?
It converts the dose you enter into syringe units. The dose itself comes from your prescriber.
Can I log a compound that is not in the list?
Yes. Type its name when you record a dose.
Does Reko sell or recommend compounded medicines?
No. Reko sells no medicine and recommends no pharmacy or brand.
Reko records what you decide. It does not suggest a dose and it is not medical advice.
- U.S. Food and Drug Administration. Compounding and the FDA: Questions and Answers. Page current as of 16 September 2025. Checked 2 November 2026.