Learn · five short missions · about 5 minutes
Peptides arrive as a dry powder in a small vial. Before anyone can measure a dose, water gets mixed in — and that one step is where most mistakes happen. You're going to learn the whole thing by doing it, one small task at a time.
The one idea behind everything: the powder is the medicine. The water is just the ride it travels in. Adding water never changes how much medicine is in the vial — only how watered-down each drop is.
Here's what a vial label usually shows. Which number tells you how much medicine is inside?
Doses are often written in a smaller unit: mcg (micrograms). Your vial speaks in mg. How many mcg fit inside 1 mg?
Think of drink powder: one scoop in a small glass is strong, the same scoop in a big pitcher is weak — but it's still exactly one scoop. Now you mix. This vial holds 5 mg of powder. Drag the water slider until every mL of liquid carries 2.5 mg.
Small doses are measured with the little 1 mL syringe — the kind with 100 tiny lines on the barrel. Each line is called a unit, and all 100 of them together make 1 mL.
Halfway up the syringe is 0.5 mL. How many little lines is that?
The final mission uses everything at once. Your vial: 5 mg of powder mixed with 2 mL of water. The dose you were told to take: 250 mcg. Drag the plunger to the right line, then check.
Finish the five missions above and this practice area opens up.
mg and mcg are 1,000 apart. Before touching anything, say it out loud: “250 mcg — that's 0.25 mg.”
The line you pull to depends on how much water went in. A freshly mixed vial never inherits yesterday's number.
A dose that lands on line 2 is a squint; the same dose with more water lands on line 20. Same medicine, friendlier ruler.
Work out the line, then cross-check with “each line carries X mcg.” If the two answers disagree, stop and find out why.
Educational content only. This page teaches the arithmetic of mixing and measuring — it is not medical advice and says nothing about whether, what, or how much anyone should take. Real dosing decisions belong with a prescribing clinician or pharmacist, who should verify any calculation before it's used.