BD SYRINGE 1mL L/SLIP TUBERCULIN LATEX FREE x BOX100

Understanding the difference between a tuberculin syringe and an insulin syringe:

They are made for administration of specific measurements of either insulin or the antigen for TB testing called PPD (Purified Protein Derivative). Both types of syringes are calibrated into "units". Unit measurements are fixed measures but specific to each type of medicine/solution as to their volume. A unit of insulin is not the same thing as a unit of TB antigen, so the TB syringe can not be used in the place of an insulin syringe.

Insulin is administered with the insulin syringe "subcutaneously" (under the skin) in the subcutaneous (sub Q) tissue. The needle is slightly longer than that on a TB syringe. The antigen solution is administered in the TB test "intradermally" (within the skin/between the layers of the skin) instead of under the skin, so the needle is shorter.

The amount of liquid in a dose of TB antigen is much smaller than the amount usually given of insulin. Therefore, the barrel of the TB syringe is smaller in diameter to allow such very small amounts (drops) of antigen to be measured.

In addition, insulin syringes come in two scales of measurement: U-100 and U-40. This on the label of the syringes indicates which type of insulin they are made to measure and administer. The insulin vial will also be marked either "U-100" or "U-40". One strength is 100 units of insulin per mL and the other is 40 units of insulin per mL. A different insulin syringe is need to measure U-100 than the type used to measure U-40. Unit calibration on the syringe used must be matched to the "strength" of the insulin being used. U-100 insulin has 1/100 of a mL volume per unit (equal also to 1/100 of a cc). U-40 insulin has 1/40 of a mL volume per unit.