Lowering glucose levels in a diabetic cat typically involves a combination of the right diet, insulin or oral medication, weight management, and consistent monitoring. Nearly half of diabetic cats can actually achieve remission, meaning they no longer need medication, when treatment starts early and is managed well. The approach depends on how severe the diabetes is and whether your cat has other health issues, but the core strategies are the same.
Why Cat Blood Sugar Gets Too High
Cats develop diabetes in a way that resembles type 2 diabetes in humans. Their bodies either stop producing enough insulin or their cells stop responding to it properly. Insulin is the hormone that tells muscles, the liver, and fat tissue to pull glucose out of the bloodstream and use it for energy or storage. When that signaling breaks down, glucose builds up in the blood instead.
Obesity is the single biggest risk factor, and the numbers are striking: each excess kilogram of body weight causes a 30% decline in insulin sensitivity. In an overweight cat, fat cells become enlarged and inflamed, releasing substances that interfere with insulin’s ability to do its job. The pancreas tries to compensate by producing more insulin, but eventually it can’t keep up. That’s when blood sugar climbs and clinical diabetes sets in, with symptoms like excessive thirst, frequent urination, weight loss despite a good appetite, and lethargy.
Switch to a High-Protein, Low-Carb Diet
Diet is one of the most powerful tools for controlling glucose in cats, and it’s often the first thing a vet will address. The American Animal Hospital Association recommends diabetic cats eat a diet with at least 40% of calories from protein and roughly 12% of calories from carbohydrates. This is a dramatic shift from many standard dry cat foods, which can derive 30% to 50% of their calories from carbs.
Cats are obligate carnivores, and their metabolism is built to run on protein and fat rather than carbohydrates. A high-carb diet forces a larger insulin response after every meal, which is exactly what a diabetic cat can’t handle. Switching to a low-carb, high-protein wet food reduces the glucose spike after eating and gives the pancreas a chance to recover. The high protein content also protects against muscle loss (a common problem in diabetic cats), supports a healthy metabolic rate, and helps cats feel fuller on fewer calories if weight loss is needed.
Canned or pouch-style wet foods are generally better choices than kibble because they tend to be lower in carbohydrates. Your vet can recommend specific therapeutic diets formulated for diabetic cats, but many over-the-counter high-protein wet foods also fit the profile. Consistency matters too: feeding meals on a regular schedule, rather than free-feeding from a bowl of dry food, helps keep glucose levels more predictable throughout the day.
Insulin Therapy
Most diabetic cats need insulin injections, at least initially. This sounds intimidating, but the needles are tiny and most cats tolerate the injections well once owners get comfortable with the routine. Insulin is typically given twice daily, timed with meals.
The type of insulin matters. Insulin glargine, a long-acting synthetic insulin, is widely considered the best option for cats. It suppresses blood glucose for at least 24 hours in most cats, with peak action around 14 hours after injection. This long, steady effect provides smoother glucose control throughout the day. Lente insulin (sold as Vetsulin), a porcine-derived option, has a shorter duration of action. When given every 12 hours, there are roughly 4 hours before each injection where the insulin effect has worn off, leading to significant blood sugar spikes in many cats. Studies also suggest clinical hypoglycemia, the dangerous dipping of blood sugar too low, occurs less frequently with glargine than with lente or protamine zinc insulin.
The goal of insulin therapy is to keep blood glucose between 80 and 300 mg/dL for most of the day, with the lowest point (called the nadir) ideally landing between 80 and 150 mg/dL. Your vet will start with a conservative dose and adjust it over weeks based on glucose curves, which track how blood sugar rises and falls over an 8 to 12 hour period.
Oral Medications for Eligible Cats
Two oral medications, bexagliflozin (Bexacat) and velagliflozin (Senvelgo), are now FDA-approved for treating feline diabetes. These belong to a class called SGLT2 inhibitors, and they work in a completely different way from insulin. Instead of helping cells absorb glucose, they block the kidneys from reabsorbing glucose back into the bloodstream. The excess glucose passes out in the urine, directly lowering blood sugar levels. This also takes pressure off the pancreas and, in cats that still produce some insulin on their own, can help reverse the toxic effects of chronically high glucose.
Not every cat qualifies. The ideal candidate is an otherwise healthy, newly diagnosed diabetic cat with a good appetite and no significant complications. Cats must still be producing some of their own insulin, because without any endogenous insulin, they’re at risk of a dangerous condition called diabetic ketoacidosis. Cats with kidney disease, liver problems, pancreatitis, or those who weigh under about 6.6 pounds are not eligible. Your vet will run bloodwork to check for these issues before prescribing an SGLT2 inhibitor. For cats that do qualify, the appeal is clear: a once-daily liquid or tablet instead of twice-daily injections.
Weight Loss Improves Insulin Sensitivity
If your cat is overweight, helping them lose weight is one of the most effective ways to lower glucose long-term. Remember that 30% drop in insulin sensitivity per extra kilogram: losing even a modest amount of weight can meaningfully improve how well your cat’s body responds to insulin, whether it’s injected or naturally produced.
Weight loss in cats needs to happen gradually. Cats that lose weight too quickly are at risk for hepatic lipidosis, a serious liver condition. The high-protein diabetic diet helps here by preserving lean muscle while promoting fat loss, and the increased satiety from protein can make calorie restriction easier. Your vet will set a target weight and a safe rate of loss, usually no more than 1% to 2% of body weight per week. Interactive play and environmental enrichment that encourages movement can help, but diet is where most of the weight loss happens.
How to Monitor Glucose at Home
Home monitoring gives you and your vet a much clearer picture of how well treatment is working than occasional vet visits alone. There are two main approaches.
The traditional method uses a handheld glucometer, similar to what people with diabetes use. You prick the edge of your cat’s ear to get a small drop of blood and place it on a test strip. For a full glucose curve, this is done every 2 hours for 8 to 12 hours. It’s effective but labor-intensive, and some cats find repeated ear pricks stressful.
Continuous glucose monitors (CGMs) have become increasingly popular. The FreeStyle Libre is the most widely used CGM in cats. A small sensor, about the size of a coin, is applied to the cat’s skin (usually on the neck or between the shoulder blades) and continuously measures glucose levels for up to 14 days. The newest version, the FreeStyle Libre 3, automatically sends readings to a smartphone, so you don’t need to manually scan the sensor every few hours. Many owners and cats find this far less stressful than repeated blood draws, and it captures overnight patterns that would otherwise go undetected.
Diabetic Remission Is Possible
One of the most encouraging aspects of feline diabetes is that remission, getting to the point where a cat no longer needs any insulin or medication, is a realistic outcome. In a large study of 174 cats treated with twice-daily glargine and home monitoring, 47% achieved remission. Remission rates across different studies range from 11% to over 60%, depending on the treatment protocol and how quickly therapy was started.
Remission is defined as maintaining normal blood glucose (at or below 117 mg/dL on a casual, non-fasting check) for at least 2 to 4 weeks after stopping insulin, with no clinical signs of diabetes. Early, aggressive treatment gives the best chance. When glucose is brought under control quickly, the pancreas gets relief from the constant demand to overproduce insulin. In many cats, the insulin-producing cells recover enough to manage on their own, especially if the underlying cause (often obesity and a high-carb diet) is also addressed.
Cats in remission still need periodic glucose checks, because relapse can happen, particularly during illness or weight gain. But for nearly half of treated cats, diabetes is a reversible condition rather than a lifelong sentence.
Recognizing Low Blood Sugar Emergencies
Whenever you’re actively lowering a cat’s glucose with insulin, there’s a risk of dropping it too far. Hypoglycemia, or dangerously low blood sugar, is the most serious short-term complication of diabetes treatment, and it can be fatal if untreated.
Signs to watch for include weakness, lethargy, vomiting, loss of coordination, tremors, seizures, and in severe cases, coma. If your cat shows any of these symptoms, offer their regular food immediately. If they won’t eat, rub honey, corn syrup, or a dextrose gel (available at most pharmacies) directly onto their gums and get to a veterinarian right away. Do not put your fingers or force anything into the mouth of a cat that is seizing or unconscious. Having a glucose source on hand at all times is a basic safety measure for any cat on insulin therapy.