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Health & Wellness

Hypoglycemia in dogs: How to know if your dog has low blood sugar

And when to see a vet to treat hypoglycemia.

Diabetes in dogs occurs when a pup suffers from either a relative or an absolute shortage of insulin. This lack of insulin results in a condition called hyperglycemia, or increased blood sugar level. Hypoglycemia, or low blood sugar, is the opposite problem and may be more common than you think.

Low blood sugar in dogs

Hypoglycemia describes situations where a pet’s glucose, or blood sugar, drops below 70 mg/dL, either because of decreased sugar production, increased utilization or increased loss. 

“Glucose is an important source of energy for the body, so when blood sugar drops, many organ systems are affected,” Dr. Kelly Diehl, DVM, MS, Dipl. ACVIM (SAIM), a former vet and the senior scientific programs and communications adviser at Morris Animal Foundation, says.

Low blood sugar is a common occurrence in dogs (and cats, too) and has many different causes, including (but certainly not limited to):

  • End-stage liver disease
  • Increased insulin levels, due to either insulin producing tumors or accidental overdose of insulin injections
  • Glycogen storage disease
  • Systemic infection
  • Cancer
  • Hypoadrenocorticism (Addison’s disease)
  • Starvation or malnutrition
  • Xylitol toxicity (found in some sugar-free candies and gums)

RELATED: Hypoglycemia in cats and what it means for blood sugar levels

Hypoglycemia symptoms in dogs

Many of us have felt the effects of low blood sugar. Just like when you skip breakfast, your dog may feel dizzy, weak, tired or uncoordinated if their blood sugar is too low. These signs may be especially noticeable after exertion, such as exercising or excitement.

“If a dog’s blood sugar drops to very low levels, they can have seizures, which is a very serious problem that requires immediate attention,” Dr. Diehl says. “When low blood sugar is due to another problem, such as liver disease, cancer, toxin ingestion or severe infection, the dog’s symptoms will vary.”

Your veterinarian can perform a quick blood test on a dog to determine their blood sugar level the same way diabetics can. Finding a blood sugar level below normal along with common signs usually confirms hypoglycemia, but it doesn’t give an underlying reason for the problem.

Your veterinarian will consider your dog’s age, breed and sex when diagnosing the cause of their hypoglycemia. Some underlying causes for hypoglycemia are more common in certain breeds, or in pets of a certain age. For example, some small-breed dogs can have transient hypoglycemia, which means their blood sugar drops after eating.

How to treat low blood sugar in dogs

Treating hypoglycemia will vary depending on the dog’s underlying cause. Puppies may have episodes of hypoglycemia and will often grow out of the problem as they mature. In most dogs, getting the cause under control will solve any recurring low blood sugar issues, but some pets need to be hospitalized for intravenous (IV) fluids that contain an extra sugar boost. 

“Treatment depends on the degree of hypoglycemia and the signs experienced by the pet,” Dr. Diehl says. “In the case of seizures, intravenous glucose, as well as other supportive care measures, are needed. But, in cases where the low blood sugar is mild, sometimes something as simple as feeding your dog is enough to correct the problem.”

Karo syrup can be administered orally at home in a pinch if you have a dog or cat prone to hypoglycemic episodes, but be sure to ask your veterinarian for advice on at-home care before giving them any medications, foods or supplements.

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The Dig, Fetch Pet Insurance's expert-backed editorial, answers all of the questions you forget to ask your vet or are too embarrassed to ask at the dog park. We help make sure you and your best friend have more good days, but we’re there on bad days, too.

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