U-40 Syringe
A U-40 syringe is an insulin syringe calibrated at 40 units per milliliter, where 1 unit equals 0.025 mL. It is less common than U-100 and requires different dosing math.
Overview
U-40 syringes are calibrated for veterinary insulin products that are formulated at 40 units/mL concentration, versus the 100 units/mL used in human insulin. Using a U-40 syringe with peptide dosing math designed for U-100 will result in drawing 2.5 times more volume than intended — a significant overdose error. When calculating peptide dose in syringe units on a U-40 syringe: Units = (Dose in mcg ÷ Concentration in mcg/mL) × 40. If research is conducted using U-40 syringes, this must be specified explicitly in any calculator or dose calculation.
Related Terms
Related Calculators
Frequently asked questions
Who uses U-40 syringes?+
U-40 syringes are primarily used in veterinary medicine where insulin is formulated at 40 units/mL. They are uncommon in human peptide research contexts.
What happens if I use U-40 math with a U-100 syringe?+
You would draw 2.5× less volume than intended, significantly underdosing. Always identify your syringe type and use the correct conversion.
How many mL is 10 units on a U-40 syringe?+
10 units ÷ 40 units/mL = 0.25 mL. Compare to U-100 where 10 units = 0.1 mL — a meaningful difference.