Diabetic complications in dogs

Diabetes is a relatively common disease in people and is being recognized more frequently in pets. If untreated the disease has serious effects and will ultimately result in the death of your pet. The good news is that most diabetic animals can be successfully treated and many live normal, happy lives. However, caring for a diabetic pet takes a good deal of time and effort to make sure their disease is well controlled, and a poorly controlled disease can lead to a variety of complications.

 

©Jane Dobson

High levels of sugar in the blood can result in consequences which can severely impact your pet’s quality of life. These include the problems you probably first noticed in your pet such as weight loss, drinking excessively and increased appetite. Dogs with poorly controlled diabetes also tend to have poor general health and low immunity, which can increase the risk of infections. The presence of diabetes can also lead to complications when a dog develops another health problem, whether it is a simple gastrointestinal upset or something more serious. In that case, diabetic pets may become suddenly very ill with high blood sugar levels, and they might develop a condition called ketoacidosis or ketosis. This is a life-threatening emergency and urgent veterinary help might be needed to save your pet’s life. Therefore, it is recommended that your pet receives prompt veterinary attention at the first sign of any illness.

Hypoglycemia (low blood sugar)

If blood sugar levels drop too low (this is often called a ‘hypo’ attack), your pet may have episodes of wobbliness, confusion and ultimately could collapse. Some diabetic dogs are more prone than others to low blood sugar. Most episodes of low blood sugar only result in mild signs such as confusion or wobbliness; however, in some cases, low blood sugar levels can result in more serious signs of seizures, coma and death. These attacks can occur because of overdose of insulin or under feeding. Hypoglycemia may cause clinical signs of hunger (not as obvious in dogs), hiding, nervousness, restlessness, disorientation, ataxia and coma which can be life-threatening.

If your pet suffers a hypo attack your veterinarian will recommend dropping the insulin dose to three-quarters or less than your pet was getting before. If hypoglycemia is present for a long time, then other complications can develop.

Diabetic ketoacidosis (DKA, ketosis)

Diabetic ketoacidosis (DKA) is most often seen in dogs that have not yet had their diabetes recognized but can also occur in dogs receiving insulin treatment if the dose of insulin is too low or the insulin is not working properly. In almost all cases there is another disease or condition in addition to the diabetes that triggers the DKA to develop. In normal animals, blood sugar levels rise after eating. Insulin is released and this helps the tissue to take up the sugar from blood to use as energy source. In diabetic animals the insulin is not present, or not working effectively, and the cells cannot use the sugars. Tissues are starved of fuel and so they switch to use fats instead of sugar. The rapid breakdown of fat to use as an energy supply, results in the production of ‘ketones’ which can be toxic to the body.

Over a short period of time, your dog may become unwell with vomiting and depression. There may also be signs of another underlying condition, such as a urinary tract infection or liver disease with yellowing of skin and gums (jaundice), or kidney disease. The signs of DKA usually develop within a few days and your pet may go downhill very rapidly.

Cataracts

Diabetic dogs are fortunately not prone to the same long-term complications as people with diabetes. However, a common complication of diabetes in dogs is blindness due to cataract formation. A cataract is formed when protein builds up in the lens of the eye causing a milky appearance. This can initially cause blurred vision, but as the whiteness gets more intense, light is prevented from reaching the back of the eye and your dog may become blind. Cataract formation can occur slowly or quickly. Inflammation associated with the cataracts typically requires life-long treatment. Vision can be restored by surgical removal of the cataracts.

Diabetic retinopathy

Diabetic retinopathy has occasionally been reported in cats and dogs, but it fortunately does not cause the same problems as in people with diabetes. High blood sugars cause damage to small blood vessels and over time, if your pet is not well stabilized, there may be a reduced blood supply to the retina at the back of eye. The retina is the area of the eye that detects light and so if it is damaged vision may be affected. Blindness due to damage to the retina is rare in diabetic animals.

To reduce the risk of your pet developing other conditions alongside its diabetes it is important to try to keep blood sugar levels well controlled. This can only be achieved by careful monitoring and regular discussion with your veterinarian on how your pet is progressing.