Diabetes mellitus is a long-term condition in which a dog or cat cannot move sugar from the bloodstream into the cells that need it. The earliest signs are easy to miss: drinking noticeably more, urinating more, losing weight despite a healthy appetite, and low energy. Those changes warrant bloodwork rather than waiting to see whether they settle.
What diabetes mellitus actually means for your pet
Food is broken down into glucose, a simple sugar that circulates in the blood. Insulin, a hormone made by the pancreas, is the key that lets glucose move out of the blood and into cells where it can be used for energy.
In diabetes mellitus, either the pancreas does not produce enough insulin or the body stops responding to the insulin it makes. Glucose builds up in the bloodstream instead of feeding the cells, then spills over into the urine and pulls water out with it. That single mechanism explains almost everything you see at home: the extra drinking, the extra urinating, and the weight that falls away even while the food bowl is emptied.
Dogs and cats tend to arrive at the same problem by different routes. Dogs more often have the insulin-deficient form, while in cats a blunted response to insulin is more common, which is one reason body weight matters so much in feline cases.
The four early changes that get explained away
Diabetes rarely announces itself. It edges into a household, and each change on its own has a perfectly reasonable innocent explanation, which is precisely why it gets overlooked.
- Drinking much more. You are refilling the water bowl more often, the bowl is dry by morning, or your pet has started hovering at the tap. This gets blamed on warm weather or a salty treat.
- Urinating much more. Heavier or more frequent clumps in the litter box, asking to go out overnight, or accidents from a pet who has been reliable for years. This gets blamed on ageing or on behaviour.
- Losing weight while eating well. Your pet is hungry, sometimes hungrier than usual, yet feels bonier over the spine and hips. This one is genuinely tricky, because owners often read it as a diet finally working.
- Lethargy and a dull coat. Less interest in walks or play, and a coat that looks flat, greasy, or scurfy. In cats, grooming often falls off first, so the coat looks unkempt in a pet who was always fastidious.
None of these confirms anything on its own. Each one is a reason to book an exam and have lab work run, because unexplained weight loss and persistent lethargy also appear in our rundown of the warning signs of cancer in pets, and several ordinary conditions can look identical from the sofa. Testing is what separates them.
Fraser Heights is a family neighbourhood full of busy households, and the household detail is what usually catches this early. Someone notices the water jug is being emptied twice as fast, or that the litter box needs changing on a Wednesday when it always used to last until the weekend. In a multi-pet home, take a moment to work out which animal is actually at the bowl before you dismiss it.
Dogs and cats show it differently
Beyond the shared four, each species has a giveaway of its own, and both are frequently the thing that finally brings a family in.
In dogs, the eyes can change fast. Cataracts may form over weeks, so a dog whose eyes looked clear last month now has a cloudy, bluish-white look to the lens and starts bumping into furniture or hesitating on stairs at dusk. Sudden cloudiness in an adult dog is always worth an urgent look.
In cats, watch the walk. A cat with long-standing high blood sugar may drop onto the hocks, so the back legs look flat to the floor rather than up on the toes, and jumping onto the counter becomes a two-stage effort. Owners often describe it as their cat walking like a rabbit.
In either species, vomiting, refusing food, weakness, or breath with an unusual sweet or acetone smell suggests a more advanced and more urgent picture, and that combination needs same-day attention rather than a wait-and-see approach. Vomiting has many causes, and our guide on why a dog vomits and when to see a vet walks through the general sorting; when it arrives alongside heavy drinking and weight loss, treat it as a call-us-now situation. If we are closed, contact a 24-hour veterinary facility in the Lower Mainland.
Risk factors worth discussing
Diabetes is not caused by one thing, and plenty of affected pets have no obvious risk factor at all. Still, some patterns are worth raising at your next visit.
- Age. Most cases show up in middle-aged and older dogs and cats, which is why baseline bloodwork becomes more valuable as pets get older.
- Body condition. Excess weight reduces how well the body responds to insulin, and this matters especially in cats.
- An indoor, low-activity life. A cat who spends the day sleeping on a sunny windowsill burns very little, and the weight creeps on quietly.
- Breed and family history. Several dog breeds are over-represented, so ask specifically about yours.
- Other conditions and medications. Some hormonal conditions and some prescribed medications influence blood sugar, so bring a complete list of everything your pet takes, including supplements.
Weight is the risk factor you can genuinely influence, and it is easier to hold a good body condition than to reverse a gain. Realistic portioning, honest treat accounting, and a plan suited to your pet’s age are what our nutrition counselling is for. Regular checkups through our wellness program also give us a weight trend over time, and a trend is far more informative than a single number.
What checking for diabetes usually involves
The work-up is straightforward and mostly non-invasive, and it is aimed as much at ruling other things out as at confirming a suspicion.
It generally starts with a full physical exam, a careful history of what you have noticed at home, and an honest weight compared against previous visits. From there, a blood sample measures glucose along with a broader panel that looks at the kidneys, liver, and other organs, since several conditions produce the same increased thirst and urination.
A urine sample is the other half of the picture. It shows whether glucose is spilling into the urine, whether ketones are present, and whether a urinary tract infection is complicating things, which is common in pets with high urine sugar. Your veterinary team will either collect a sample at the visit or explain how to bring one from home.
Cats have one extra wrinkle. Stress alone can push a cat’s blood glucose up temporarily, so one high reading in the exam room is not the end of the story, and a longer-term blood marker may be used to see past that. Blood and urine testing are run through our in-house pet diagnostics, so most families leave with real information the same day rather than waiting on an outside laboratory.
Management is a long-term partnership
Here is the honest and reassuring part. Diabetes is a serious diagnosis, and it is also one that many dogs and cats live with comfortably for years when it is managed consistently. What it asks of you is routine rather than heroics.
Treatment is directed by your veterinarian and commonly includes insulin therapy, along with a steady feeding schedule and a consistent diet chosen for your individual pet. Never start, stop, change, or adjust any diabetes treatment on your own, never use a product intended for a person, and call us before making any change, because the margin for error with blood sugar is genuinely small.
Your part is observation. Track water intake, appetite, weight, energy, and litter box or bathroom output in a simple note on your phone, because those numbers tell us far more between visits than memory does. Recheck appointments and repeat bloodwork are how the plan gets tuned, and that ongoing relationship sits within our chronic condition management. It also means any planned procedure needs coordinating in advance, so if a dental cleaning is on the horizon, tell us about the diabetes when you book rather than on the day.
One note for cat owners. Some cats, with early and consistent veterinary-directed care, reach a stretch where treatment can be reduced or paused. That is a real possibility your veterinarian can explain for your individual cat, but it cannot be promised, and it is not the expected path in dogs.
Frequently Asked Questions
How much drinking is too much for my dog or cat?
A sustained, obvious increase is the thing to act on, rather than any exact figure. If you are refilling the bowl noticeably more often, the bowl is empty every morning, or your pet has started drinking from taps, tubs, or puddles when they never did, that pattern warrants bloodwork. A useful step is to measure what you put down for two or three days so we have real numbers.
My cat is walking flat on his back legs. Is that related?
It can be, and it should be checked promptly. Cats with long-standing high blood sugar can develop a weakness that drops them onto their hocks, giving a flat-footed, crouching walk and a reluctance to jump. It is not the only cause of a changed gait in a cat, so an exam and lab work are how we tell the possibilities apart.
Can diabetes in pets be cured or reversed?
It is generally treated as a lifelong condition to manage, not to cure. Many dogs and cats do very well over years with consistent care and monitoring. Some cats reach a period of remission where treatment can be reduced or paused, which is a conversation to have with your veterinarian about your own cat rather than something to count on in advance.
Does my pet need to be overweight to develop diabetes?
No. Weight is a meaningful risk factor, particularly in cats, but plenty of lean dogs and cats are diagnosed, and weight loss is itself one of the classic early signs. Judge the change, not the shape. A pet who is dropping weight while eating well should be seen regardless of what the scale says today.
What should I do if I have noticed these changes but my pet seems otherwise fine?
Book a regular appointment and mention exactly what you have seen and when it started. Pets often look and act normal in the early stage, which is the best possible time to find this, because a plan started early is easier on everyone. Bring your notes on drinking, appetite, and weight, and call us at (604) 359-6464 sooner if vomiting, refusing food, or weakness appears.
Drinking more than usual? A straightforward test can answer it
The changes that matter here are small and slow, which is exactly why they get written off as your pet getting older. If the water bowl is emptying faster, the litter box is heavier, or weight is dropping while appetite holds up, book an appointment rather than watching another month go by. Our Fraser Heights team can check blood and urine through pet diagnostics and give you a clear answer.
Published by the team at Ridgeview Animal Hospital.
This article is provided for general educational purposes only and is not a substitute for an in-person veterinary exam, diagnosis or treatment. If you have an urgent concern about your pet, please contact Ridgeview Animal Hospital directly, or your nearest emergency veterinary hospital outside our clinic hours.
Ridgeview Animal Hospital
10833 160 Street, Surrey, BC V4N 1P3
Phone: (604) 359-6464
Hours: Monday to Friday 8:30 AM to 7:00 PM
Saturday: 9:00 AM to 4:00 PM
Sunday: Closed