A syringe consists of a plunger that fits snugly within a tube. The end of the tube has a hole that's fitted with a hypodermic needle. A syringe is a common method of delivering insulin to diabetics, who must frequently inject themselves every day. Several types of diabetic syringes are commonly used, depending primarily on the amount of insulin that the diabetic must inject.
U100 Syringe
A U100 syringe is the most common diabetic syringe and will deliver U100 insulin. This preparation of insulin contains 100 units of insulin in a volume of 1 milliliter (ml) of solution. A U100 syringe has graduation markings that indicate the number of units of insulin. Most syringes of this type have graduation markings with 2-unit increments (2, 4, 6) although some models have 1-unit increments (1, 2, 3.) A U100 syringe normally has black graduation markings and an orange needle cover.
U500 Syringe
A U500 syringe delivers U500 insulin. This preparation of insulin contains 500 units of insulin in a volume of 1 ml of solution. Most syringes of this type have graduation markings with 2-unit increments although they may also have 1-unit increments. A U500 syringe is used by diabetics with high insulin resistance who need more than 200 units per day. This type of syringe is therefore quite rare.
U40 Syringe
A U40 syringe delivers U40 insulin, which contains 40 units of insulin in 1 ml of solution. Most syringes of this type have graduation markings with 2-unit increments although they may also have 1-unit increments. They're typically used to inject diabetic pets with insulin, but they aren't currently available in the United States. A U40 syringe most often has red graduation markings with red needle caps.
Additional Sizes
Most diabetic syringes have a capacity of 1 ml but several other sizes also exist. A syringe that delivers up to 25 units of insulin has a capacity of 0.25 ml. A syringe that delivers up to 30 units of insulin has a capacity of 0.30 ml. A syringe that delivers up to 50 units of insulin has a capacity of 0.5 ml.
