Diabetes mellitus can affect dogs at any age, but early detection is crucial for maintaining their health and happiness.
Annual wellness checkups are vital for spotting diseases early. However, knowing the signs and symptoms of diabetes in dogs allows you to identify potential issues between visits and seek veterinary care promptly.
Remember that diabetes symptoms can resemble those of other diseases. For instance, increased urination and thirst can also indicate kidney or liver disease, while increased appetite might be due to hyperthyroidism or certain cancers.
If you're ever uncertain, it's best to take your dog to the vet for a comprehensive evaluation to check for diabetes or other conditions.
Below are the most common symptoms of diabetes in dogs.
Increased Frequency Of Your Dog's Urination
You might notice puddles on the floor or your dog asking to go outside more frequently to urinate.
If you notice that your dog is drinking more water than usual, it could be an early sign of diabetes. This increased thirst is typically paired with more frequent urination. In diabetic animals, their kidneys can't manage the excess sugar in their blood, leading to its excretion through urine.
Excessive Water Consumption By Your Dog
Excessive thirst (polydipsia) is connected to frequent urination, but not in the way you might expect.
"Owners often assume their dog is urinating more because they're drinking more, but it's actually the opposite," says Dr. Romine.
"As the dog urinates more frequently, they become dehydrated and start drinking more water to compensate."
Unusually High Appetite In Your Dog
A diabetic dog might develop a constant appetite (polyphagia) due to an insulin imbalance. Insulin, a hormone produced by the pancreas, regulates blood sugar levels.
If your dog has diabetes, it might show signs of increased hunger. While dogs often seem hungry even when they are not, a dog that is eating more than usual yet maintaining or losing weight could be exhibiting symptoms of diabetes.
Weight Loss Despite Normal Eating Habits In Your Dog
Several conditions can lead to weight loss in dogs, such as cancer, gastrointestinal issues, liver disease, and kidney disease, according to Dr. Romine.
When weight loss—whether gradual or sudden—occurs despite a normal appetite, it may indicate diabetes.
"Without insulin effectively transporting glucose to the brain, heart, and other vital organs for energy, the body starts breaking down fat and muscle for fuel, resulting in weight loss," Dr. Romine explains.
Cloudy Appearance In Your Dog's Eyes
Dr. Romine states that up to 80% of dogs with diabetes mellitus will eventually develop cataracts. Cataracts are a common long-term complication in diabetic dogs.
In a healthy dog, the lens absorbs glucose from the eye fluid and converts the excess into sorbitol. "When there is a high glucose level, a large amount of sorbitol is produced. Sorbitol attracts water, which enters the lens and distorts the fibers, preventing light from passing through."
This process can make your dog's eyes appear cloudy.
Declining Vision In Your Dog
Due to cataract formation, diabetic dogs face a higher risk of blindness.
When a cataract entirely blocks light from reaching the retina, it leads to vision loss, explains Dr. Romine. "The positive news is that most blind dogs adapt well as long as secondary inflammation from cataracts is managed. They depend on their strong senses of smell and hearing to navigate their surroundings."
In some cases, blindness can be reversed through surgery to remove the abnormal lens.
Blindness and cataract formation can develop over weeks, months, or even in as little as 24 hours. This can occur at any stage of diabetes.
Dull Coat And Skin In Your Dog
Untreated diabetic dogs often exhibit poor coat and skin quality.
"When a dog isn't receiving the necessary nutrition due to ineffective insulin and is chronically dehydrated from increased water loss in the urine, their coat can lose its shine and thin out. They may also develop dandruff and dry, scaly skin," explains Dr. Romine.
Insulin therapy typically improves these conditions, as "adequate energy and nutrition are then available for maintaining healthy fur, not just critical organ function," Dr. Romine adds.
Unexplained Vomiting In Your Dog
Vomiting is usually not seen in uncomplicated diabetes, says Dr. Behrend. "If diabetes is left untreated, the dog can develop diabetic ketoacidosis (DKA), which presents with vomiting, lethargy, and poor appetite. This is an emergency requiring hospitalization." Other DKA symptoms in dogs include panting and weakness.
DKA occurs when blood sugar is very high and little to no insulin is moving glucose into the tissues, explains Dr. Romine. "The body starts producing ketones for energy, but this isn't sustainable; the blood becomes acidic, and the body's enzymes start to malfunction."
In some DKA cases, you might notice a distinct smell on your dog's breath, similar to nail polish remover, says Dr. Behrend. However, this odor is uncommon, and not everyone will detect it.
Lethargy And Disinterest In Activities In Your Dog
"Some dogs may become less interactive with their families due to a lack of energy and will tire more quickly after playing or going for walks," says Dr. Romine.
According to Dr. Romine, when glucose is trapped in the bloodstream and can't enter the tissues, the body is deprived of the energy it needs. "High blood sugar can also lead to electrolyte imbalances, including low levels of sodium, potassium, and phosphorus, which disrupt normal nerve function."
Stiffness Or Weakness In Your Dog
Your dog may stumble, appear stiff, or have difficulty lying down.
"Dogs with diabetes can experience muscle weakness due to insufficient glucose reaching their muscles," says Dr. Romine.
Another less common cause is diabetic neuropathy, which can result in chronic or progressive hindlimb weakness, muscle atrophy, knuckling, and general weakness.
Though rare, diabetic dogs may develop dropped hocks, a condition where the rear legs are closer to the ground than normal, notes Dr. Behrend. "Owners might notice their dog standing or walking unusually, although it's quite subtle."
Importance Of Early Intervention
Recognizing the signs of diabetes in dogs and consulting your veterinarian early can make a significant difference.
Dr. Romine says diabetes in dogs is typically manageable, and "most diabetic dogs can thrive once an insulin routine is established."
While diabetes is more common in older dogs, it can still affect puppies. Always consult your vet if you see anything unusual, regardless of your dog's age.
