How syringe units work for peptide dosing
Peptide calculators often return both mL and syringe units. The mL is the actual volume; the unit number is a marking system printed on certain insulin syringes.
Key takeaways
- U-100 means 100 syringe units equal 1 mL.
- A 0.1 mL draw is 10 units on a U-100 syringe.
- Changing syringe type changes the unit number even when the mL volume is the same.
Units are a syringe scale, not a peptide dose
The word units can be confusing because some medicines use biological units. On an insulin syringe, units are a volume scale. A U-100 syringe has 100 markings per mL.
That means the calculator must solve dose volume first, then translate the mL volume into the marking shown on your syringe.
- 0.05 mL = 5 units on U-100
- 0.10 mL = 10 units on U-100
- 0.50 mL = 50 units on U-100
Why syringe type matters
U-40, U-50, and U-100 syringes use different unit scales. The same liquid volume can show a different unit count if the syringe type changes.
Always enter the syringe type you actually use. If you switch syringes mid-protocol, re-run the calculation before drawing.
Use mL as the anchor
When checking the math, treat mL as the stable answer and units as the syringe translation. This makes it easier to catch mistakes when a calculated unit count looks unusually high or low.