Diabetes mellitus

Diabetes is a relatively common disease in older people and is being recognized more frequently in older pets. If untreated the disease has serious effects and will ultimately result in the death of your pet. The good news is that the majority of diabetic animals can now be treated and may live normal, happy lives if you are prepared to invest time and money in their care.

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Diabetes is a disease caused when there is not enough insulin in the body. Insulin is a hormone which keeps blood sugar (glucose) at an optimum level. When there is a lack of insulin, sugar from food builds up in the blood and eventually starts to appear in the urine.

Animals with diabetes have high blood sugar levels and lose sugar in their urine. They are more thirsty than normal and often lose weight despite having a good appetite. If the condition is untreated, liver disease, problems walking or other illness may develop. If the early signs of diabetes are missed, more serious signs such as vomiting and depression may develop. If diabetes is left untreated for weeks or months your pet could go into a coma and die.

If your cat has been diagnosed as a diabetic you may be wondering if you have done something wrong. Unfortunately some cats are just more likely to develop the disease than others. Male cats are most likely to get diabetes but any cat can be affected. Obese cats are slightly more likely to develop the disease, but there are many obese cats who do not develop diabetes. Some other diseases can cause diabetes to develop and your veterinarian will check to make sure your cat is not suffering from anything else. In a few cases treating the other disease will make the diabetes go away for a while, but it is quite likely to come back again later.

Most diabetic cats require regular insulin injections to control their blood sugar levels. Diabetes rarely goes away completely and so these injections must be given on a regular basis (usually once or twice a day), for the rest of your cat’s life. Your veterinarian may need to help you work out a new diet and management plan for your cat. Injections should be given at set times each day but this can be arranged so that it fits into your usual schedule. Once the whole treatment schedule has been set you will have to stick to it in the future.

Most diabetic cats will need insulin injections to treat their diabetes at some stage. In some obese cats, weight loss may control their diabetes for a while. A few other cats can be managed by careful weight control and by giving tablets which lower blood sugar (hypoglycemic drugs). Although you may be worried about having to give your cat injections – most owners find that, with practice, it is easier to give their cat an injection than a tablet.

Insulin is a protein and (as with any other protein), can be digested. If insulin were given as a tablet, the tablets would be digested by the acid in the stomach and the insulin would have no effect. Insulin injections are given under the skin and do not hurt. Vetpens, similar to the pens used in human diabetes, are now available for dogs and cats.

Most people are naturally concerned that they will be unable to give injections to their pet. Your veterinarian will teach you how to do this and within a few weeks most owners of diabetic pets are happy to give the injections at home. Until you are confident your veterinarian will probably see you every day at the veterinary surgery and help you give the injections.

Your pet should be regularly monitored to make sure it doesn’t gain or lose weight. Your veterinarian needs to examine your pet regularly and review their notes to see how your pet is progressing. They will probably ask you to monitor how much your cat drinks to help monitor progress. At other intervals your veterinarian may want to take blood samples from your cat – and may need to keep your pet in hospital for a day to do this. If you have any concerns about any aspect of your pet’s treatment discuss them with your veterinarian.

There are two important complications to be aware of:

• Low blood sugar (hypoglycemia) – If this is untreated it may result in permanent brain damage. Symptoms come on quickly. The main ones are restlessness, confusion, tremors, twitches, convulsions or coma. Sugar (or better still glucose, which can be bought from your veterinarian or a chemist) should be given by mouth, dissolved in water or as lumps. If your pet is still awake you can offer glucose with food if they will eat voluntarily. Contact your veterinarian immediately if these signs develop.
• High blood sugar (hyperglycemia) – This usually develops more gradually and your pet may become unwell or start to be sick over several days. As the disease progresses your pet may go into a coma, but will not get better if you give sugar solutions. Contact your veterinarian immediately if your pet is unwell and they will probably want to take them into hospital.