the part nobody writes down
How to dose
The arithmetic, the syringe, the mixing, and the storage. No compound-specific doses live on this page; those are on each dosing guide.
These dosages are a helpful guide, not a prescription. Every clinician is expected to do their own due diligence before prescribing.
The math
Two lines cover every powder vial.
Concentration
mg per mL = vial amount (mg) ÷ diluent volume (mL)
Draw on a U-100 syringe
units = dose (mg) ÷ concentration (mg per mL) × 100
A worked example, with made-up numbers
The inputs below are only an illustration of the arithmetic. They are not a dosing recommendation, and the results come from the same code the calculator uses.
- Vial 10 mg, mixed with 2 mL: 10 ÷ 2 = 5 mg per mL
- Dose 250 mcg = 0.25 mg
- Draw: 0.25 ÷ 5 × 100 = 5 units (0.05 mL)
- Doses in the vial: 40
Powder vial
Result
Draw to
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- Concentration
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- Doses per vial
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Math on the numbers above. Not medical advice; confirm concentration against the dispensed vial label.
U-100 syringes
U-100 means 100 units per milliliter.1 On a U-100 syringe that makes 100 units equal to 1 mL, and one unit equal to 0.01 mL. The scale is built around that concentration.2
Injection: 100 units/mL (U-100), a clear and colorless solution1
a U-100 syringe is made to measure U-100 insulin.2
For a peptide, a "unit" is only a volume mark on the barrel. It is not a unit of the drug, and it is not the same thing as an IU. The calculator reads the mark from the volume, so always confirm the dose in mcg or mg and the volume in mL before you draw.
Reconstitution technique
The steps below come from the instructions for use of one FDA-approved lyophilized peptide.3 They are quoted as an example of the technique. Your vial's label and the pharmacy's instructions govern, including which diluent to use.
Clean the rubber stoppers on the top of the EGRIFTA SV 2 mg vial and Sterile Water for Injection bottle with an alcohol pad.3
the Sterile Water goes down the inside wall of the EGRIFTA SV 2 mg vial instead of directly onto the powder to avoid foaming.3
Reconstitute 1 vial of EGRIFTA SV lyophilized powder with 0.5 mL of diluent (2 mg per 0.5 mL). Mix by rolling the vial gently in your hands for 30 seconds. Do not shake.3
Do not use EGRIFTA SV if it looks cloudy, discolored, or if you see particles in it.3
Storage after mixing
There is no single rule. Two approved lyophilized products show how far labels differ: one is used immediately and never stored,3 the other is refrigerated and used within a set number of days.4
After mixing, use EGRIFTA SV right away. Throw away any unused EGRIFTA SV after mixing. Do not store, freeze or refrigerate EGRIFTA SV after it has been mixed with the Sterile Water.3
Store HUMATROPE in the refrigerator between 36°F to 46°F (2°C to 8°C) before and after mixing. Do not freeze.4
HUMATROPE that has been mixed and is in liquid form must be used within 28 days.4
For a compounded vial, follow the storage and beyond-use instructions on the dispensed label. Each dosing guide has a handling section with whatever its sources say about that compound.
Titration
Titration means starting below the intended dose and stepping up on a fixed interval, so the first exposures are the smallest. The approved labels for semaglutide and tirzepatide are the clearest examples. Their steps are in the label tables on those pages, so none are restated here.
References
- 1NOVOLIN R (insulin human) injection: prescribing informationNovo Nordisk, via DailyMed. Label version published Dec 8, 2022.
- 2HUMULIN R U-500 (insulin human) injection: instructions for use and patient informationEli Lilly and Company, via DailyMed. Label version published Sep 2, 2026.
- 3EGRIFTA SV (tesamorelin) for injection: prescribing information and instructions for useTheratechnologies Inc., via DailyMed. Label version published Jul 31, 2026.
- 4HUMATROPE (somatropin) for injection: prescribing information and instructions for useEli Lilly and Company, via DailyMed. Label version published Sep 2, 2026.