Sugar diabetes is quite common in both dogs and cats nowadays. It causes your pet to drink and eat more than normal and then pass more urine. If left untreated it causes liver damage, circulatory collapse and death. Sugar Diabetes is caused by a lack of insulin, which stops the cells in the body using the sugar in the blood.
The types of diabetes in cats and dogs differ; dogs usually suffer from Type 1 diabetes, where the cells that produce insulin have died, whereas cats usually suffer from Type 2 diabetes, where the cells that produce insulin have become exhausted. Therefore the treatment and monitoring of the disease is slightly different in cats and dogs.
Although long periods of a high blood sugar level causes problems, high blood sugar levels for a short time do little damage. However low blood sugar levels (hypoglaecaemia) are very dangerous, and can cause fits and death. We therefore have to monitor the blood sugar level to make sure that we are using the right dose of the right type of insulin at the right frequency to keep the blood sugar level from being too high for long periods but ensure that it never gets too low.
In dogs, diabetes is a lifelong condition that will need to be treated with insulin injections once or twice daily for the rest of their lives. Each dog has a different response to injected insulin, so we need repeated graphs of the way the blood sugar changes after an insulin injection. This usually requires hospitalisation for the day and repeated blood glucose tests. Once the diabetes has been stabilised, we monitor your pet's progress by checking their weight regularly and measuring the amount of fructosamine in the blood, which gives us a good idea whether their blood sugar level is stable or not. We rarely measure urine sugar any more as the above tests are so much better. Fibre-rich diets and diets with a low glycaemia index help stabilise the blood sugar level, stopping big swings from high to low, but it is not possible to control diabetes with diet changes alone.
In cats, reducing the amount of carbohydrate in the diet reduces the amount of insulin the pancreas has to produce and enormously helps control the disease; indeed it is possible to control the disease through diet changes alone, as in people. However, most cats still need daily insulin injections. Again monitoring is based on doing serial blood glucose estimations, usually when hospitalised, but they can be done at home using a blood glucose recorder. Routine checks of blood fructosamine and body weight are used to check all is well once your cat is stable. Again we now rarely monitor urine sugar levels as the above tests are much more useful.