Diabetes in dogs and cats: the first signs you should not ignore

The early picture of diabetes revolves around four changes that, taken together, are highly suggestive. On their own each may have another explanation, but when they show up in pairs or as a group they call for a prompt blood and urine check.

• Increased thirst: the animal empties the bowl more often, looks for water in unusual places such as the sink or the shower, and in cats the water level drops noticeably fast.
• More frequent and larger urination: litter that needs changing more often, bigger puddles on walks, sometimes an accident indoors in a previously clean animal.
• Appetite kept or increased but weight falling: hungry yet losing weight, because the cells stay short of energy even though sugar is plentiful in the blood.
• Less energy and a dull coat: tiredness, less desire to play, a coat that loses its shine, and in cats sometimes a way of walking that sinks onto the back hocks.

Drinking and urinating more are almost always the two signs that arrive first, and it helps to quantify them. Knowing how many litres disappear from the bowl in a day, or how often the litter is changed, turns an impression into a number your vet can use. Weighing the animal every two weeks makes a loss obvious that the eye alone would miss.

Drinking and urinating more are not unique to diabetes. Several diseases share this onset, which is exactly why the diagnosis is not made by eye but with tests. Knowing the alternatives helps you take the sign seriously without panicking too soon.

In the overweight cat diabetes is especially common and has an encouraging feature: if the diagnosis is early and management is good, a proportion of cats start producing enough insulin again and can come off treatment. This is called remission, and the window to reach it narrows as the weeks pass. That is why spotting the signs early is not just a matter of convenience.

The diagnosis combines the signs the owner reports with a few targeted tests. None of the steps is complicated, but they serve to separate diabetes from lookalike conditions and to show how far the disease has already gone.

1. 1

   Examination and history

   The vet asks how long the signs have lasted, how much the animal drinks and urinates, how the weight has changed and what food it gets. Your notes on water, weight and litter are worth more here than any impression.

2. 2

   Blood glucose

   Sugar is measured in the blood. In cats the stress of the visit can raise it temporarily, so a confirmation with a test called fructosamine, which reflects the average of recent weeks, is sometimes needed.

3. 3

   Urine test

   The vet looks for sugar in the urine and for ketones, a sign of more advanced diabetes, as well as urinary tract infections, which often accompany the disease.

4. 4

   Supporting tests

   A broader blood profile checks the kidney, the liver and other hormones, to rule out the conditions that imitate diabetes and to choose the most suitable diet and treatment.

5. 5

   A shared plan

   Once diabetes is confirmed, you agree together on the type of insulin, the timing, the diet and the monitoring method, with an early follow up to adjust course.

A well managed diabetic animal lives a long and good life, but management asks for regularity. The routine rests on three pillars: insulin at the same times, meals matched to the insulin, and steady monitoring of the signs. Most owners, after the initial fright, learn the injections within a few days.

1. Keep to the schedule: insulin is given at regular intervals, usually every twelve hours, tied to meals according to the agreed plan.
2. Do not skip meals: if the animal does not eat, the usual insulin dose can push sugar too low, so with poor appetite you contact the vet before injecting.
3. Always keep a sugar source to hand: honey or glucose syrup to rub on the gums if signs of low sugar appear, such as trembling, weakness or disorientation.
4. Record daily water intake, appetite, weekly weight and any odd episodes: this data guides adjustments far more than a single reading.
5. Store insulin correctly in the fridge, do not shake it but roll it gently, and check the expiry of the vial in use.

Diet plays a different role in the two species. In cats a diet high in protein and low in carbohydrate helps control and favours remission. In dogs consistency matters most: same food, same amounts, same times, so the effect of meals on insulin stays predictable. In both, weight should be brought gradually back to normal, because obesity worsens resistance to insulin.

The most feared complication is ketoacidosis, a crisis in which the body, deprived of usable sugar, produces acidic substances that poison it. Recognising the first signs and avoiding management mistakes is the difference between a dose adjustment and an emergency.

• Repeated vomiting, total refusal of food or marked dullness in a diabetic animal: these call for immediate contact.
• Deep, rapid breathing, breath with a sweet or fruity smell, obvious dehydration.
• Marked weakness, trembling, an unsteady gait or seizures, which may mean sugar has gone too low and should be handled by rubbing sugar on the gums while you phone.
• Sudden changes in a dog's sight, which can signal the rapid onset of a diabetes related cataract.
• Any day when the animal will not eat but insulin is already due: better to call before injecting.

In most cases, though, life with a diabetic animal is made of small repeated gestures and scheduled checks, not emergencies. Home monitoring, combined with regular visits, catches problems while they are still easy to correct, and seizes the remission window in cats in good time.