Problems with regulation
In cases of poor glycemic control, a blood glucose curve should be created and every effort made to rule out other concurrent or underlying disorders.
- Discuss the daily routine—are injections and meals correctly timed? See Feeding schedule.
- Ask for a breakdown of exactly what the dog eats—perhaps the dog is receiving too many tidbits or the incorrect diet. See Nutrition.
Factors thought to contribute to a poor response to insulin therapy:
- Incorrect storage of insulin or poor injection technique
- Anti-insulin antibodies
- Insulin resistance
- Somogyi effect
- Rapid metabolism of insulin
In cases of a poor response to insulin therapy, it is important to rule out these factors first.
Ask owners to demonstrate how they inject their pet and check the following:
- Is the insulin being stored correctly?
- Is the insulin being mixed properly?
- Is the insulin being injected subcutaneously?
- Is the injection site being correctly located?
- Is the injection site being rotated?
If using a syringe:
- How long has the vial been in use?
- Is the correct dose being drawn up into the syringe?
- Is a new syringe being used for each injection?
- Have the air bubbles been removed from the syringe during dose measurement?
If using VetPen®:
- Is the insulin cartridge inserted into the VetPen properly?
- Have the air bubbles been removed from the VetPen cartridge?
- Is a new needle being used for each injection?
- Is the correct dose being chosen using the dose selector?
- Is the release button being pushed down fully so that the dose selector returns to the start line?
- Is the movement of the dose selector restricted by the way the VetPen is being held?
- Is the needle being held in the skin for at least 5 seconds after the dose selector has returned to the start line?
Antibodies may be directed either against the insulin or against other foreign proteins in the preparation. The presence of anti-insulin antibodies is common and does not usually lead to poor regulation. Antibody production is less likely if homologous insulin (same structure) is given, eg, the porcine insulin (in Vetsulin) has the same structure to canine insulin.