How do I calculate a peptide reconstitution dose?

Vialkeep is a reconstitution calculator and injection log. It performs arithmetic on numbers you enter and stores the result on your device. It ships with no dosing database, no presets and no suggested amounts. Every figure in the app is a figure you typed.

Vialkeep is not a medical device and does not give medical advice. It cannot tell you what to take or how much. Dose decisions belong to you and your clinician. Check every figure against your own arithmetic before you draw anything.

How the math works

The calculator uses the standard desired-over-have method. Two steps, both written out on screen so you can check them.

Step 1 — concentration. Dividing the vial's strength by the volume of diluent you added gives the concentration of the mixed vial.

concentration = vial strength ÷ diluent volume

Step 2 — volume to draw. Dividing your target dose by that concentration gives the volume to draw.

volume = target dose ÷ concentration

That volume is then expressed in the markings of the syringe you selected. On a U-100 insulin syringe one unit is 0.01 mL, so 100 units is 1 mL. On a U-40 syringe one unit is 0.025 mL. Vialkeep marks the fill point on a drawing of the syringe you chose. Nothing is rounded silently and no unit is converted on your behalf.

Sources

The arithmetic above is the standard method taught in the following references. Vialkeep adds nothing to it and recommends nothing.

• Dose Calculation Desired Over Have Formula Method — StatPearls, NCBI Bookshelf, National Library of Medicine. The desired-over-have method used in both steps above.
• USP General Chapter <797>, Pharmaceutical Compounding — Sterile Preparations — United States Pharmacopeia. Standards for reconstituting and handling sterile preparations.
• Insulin, Medicines & Other Diabetes Treatments — National Institute of Diabetes and Digestive and Kidney Diseases, NIH. Background on insulin syringes and their unit markings.
• Intramuscular Injection — StatPearls, NCBI Bookshelf, National Library of Medicine. Injection technique and site rotation.

The app

Calculate. Enter vial strength, diluent volume, your target dose and your syringe. Vialkeep returns the units to draw and the volume in mL, and marks the fill point on the syringe you selected, U-100 or U-40. The working is written out.

Today. A timeline of every dose due, solid through what has happened and dashed through what is ahead. Shows what is still on board, how many doses remain in the vial, and how many days that is.

Calendar. A month grid with a mark on every dose. Tap any day to log retroactively. Filter by peptide. Export the entire record as a CSV file.

Vials. Every vial you have mixed, with its concentration and a countdown to the expiry date you set yourself.

Schedules and reminders. Set a cadence and get a local notification on your device.

Common questions

Does Vialkeep tell me how much to take?

No. There is no dosing database and no peptide arrives with a suggested amount attached. Every number in the app is one you entered. There is no AI advisor and no chat.

What is the difference between a U-100 and a U-40 syringe?

They are marked in different units of volume. One unit on a U-100 syringe is 0.01 mL; one unit on a U-40 syringe is 0.025 mL. Reading a dose on the wrong syringe gives the wrong volume, which is why Vialkeep asks which one you are holding and draws that one.

Where is my data stored?

On your device, and in your own iCloud account if you have iCloud enabled. No dose, peptide name or injection site is transmitted to us. Cloud Motion Lab operates no server and receives none of this data.

Can I get my record out?

Yes. Calendar exports the entire log as a CSV file you can open in any spreadsheet.

Is Vialkeep free?

Version 1.0 is free with every feature unlocked.

Support

If a calculation looks wrong, a reminder did not fire, or an export failed, write to us and say which screen you were on and what you entered. One person reads this address and replies.