Canine Diabetes Wiki

Measurement of insulin in syringes is based on the cubic centimeter (cc) volume measurement system for injectable liquid medications. Your box of syringes is labeled as to how many cc's a syringe will hold. U100 and U40 syringes labeled as 1cc will each hold one cubic centimeter (ml) of liquid, although as the insulin strength is increased, more units will be packed into one cc. A cc (holding a milliliter of liquid) contains 40 Units of U40 insulin, 50 Units of U50 insulin, or 100 Units of U100 insulin.

It is possible, though usually not recommended, to dose U40 insulin in a U100 syringe. [1] Be careful to convert the right way. See this table.

With so many abbreviations, one can sometimes get confused. An easy way to separate units (IU) from milliliters (ml) is to think about the following: all commonly-available vials of insulin approved for humans are 10ml vials. Most insulin cartridges for refillable pens contain 3 ml of insulin each. Caninsulin/Vetsulin comes in both a standard 10ml vial and a pack of 10 2.5ml vials. Since a U100 1cc syringe holds 1 milliliter of liquid, drawing this amount from the insulin vial would fill the syringe with 100 units of insulin; that would also be 1/10 of an entire 10ml vial and 1/3 of a 3ml insulin cartridge; it would be more than 1/3 of a 2.5 ml Caninsulin or Vetsulin vial.

Milliliters and cubic centimeters (cc) are equal-1 milliliter=1 cubic centimeter or cc, [2] so there's enough insulin in a new 10ml vial to fill a 100 IU (1 cc) insulin syringe ten times. If you look at the starting dose tables for an animal weighing 100 pounds, the most units of insulin you would be giving when starting out would be 22 units.

3 10

3/10 cc U 100 insulin syringe holds a maximum of 30 IU's of insulin.

The syringe in this photo is a 3/10 syringe (this is the smallest size insulin syringe there is; the 3/10 cc syringes are often referred to as low-dose syringes) holding at most, 30 units of insulin. To give a 100lb animal 22 units of insulin, you wouldn't even fill it totally up; 22 units is between the numbers 20 and 25. You'd still have 8 units worth of "room" left in the syringe.

If a dosage looks wrong to you, DON'T BE AFRAID to ask someone for help--your vet, an animal emergency clinic, or a canine [3] diabetes message board--BEFORE you give an injection of a questionable dose. Delaying a shot if you're not sure is much safer than the alternative.

Insulin Starting Doses
Pounds converted to kilos
and rounded down to whole number
Insulin doses based on 0.25-0.50 IU per kilo,
rounded down to nearest whole or half unit [4]


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