How much water for a 5 mg vial? (reverse math)
Water (mL) = 5 mg ÷ the concentration you want (mg/mL). 5 mg in 1 mL is 5 mg/mL, in 2 mL is 2.5 mg/mL, in 2.5 mL is 2 mg/mL and in 5 mL is 1 mg/mL. This is arithmetic only; it does not tell you which concentration or amount to use. Water changes concentration, not the 5 mg total.
The math
water (mL) = vial mg ÷ target concentration (mg/mL) mcg per U-100 unit = concentration (mg/mL) × 10 Example: 5 ÷ 2.5 = 2 mL; 2.5 × 10 = 25 mcg per unit
| Target mg/mL | Water for 5 mg | mcg per U-100 unit |
|---|---|---|
| 5 | 1 mL | 50 |
| 2.5 | 2 mL | 25 |
| 2 | 2.5 mL | 20 |
| 1.25 | 4 mL | 12.5 |
| 1 | 5 mL | 10 |
Note: The 4 mL and 5 mL rows may be more water than a small vial holds; check your vial's capacity.
Math only, not medical advice. This page converts numbers; it does not recommend any compound or amount.
Draw to
10 units
= 0.1 mL · concentration 2.5 mg/mL (2500 mcg/mL) · 20 draws per vial
Concentration = 5 mg ÷ 2 mL = 2.5 mg/mL Volume = 250 mcg ÷ 2500 mcg/mL = 0.1 mL Units = 0.1 mL × 100 (U-100) = 10 units
Math only, not medical advice. Verify every number yourself.