Hypoglycemia in Puppies

Man getting licked by a puppy
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Hypoglycemia, commonly called low blood sugar, affects puppies much more often than adult dogs—even puppies that seem perfectly healthy. This condition usually happens because puppies lack sufficient glucose stores in their bodies to sustain them through stressful events or fasting periods. It can also occur because of intestinal parasites or a physical abnormality involving the liver. Untreated, low blood sugar can cause coma, seizures, and death. Small breed puppies are particularly vulnerable to hypoglycemia.

What Is Hypoglycemia?

Hypoglycemia refers to a state of low sugar in the bloodstream. Very small puppies, especially toy breeds like the Chihuahua or Pomeranian, have a higher metabolic rate and energy requirement for their mass than larger breed puppies and adult dogs. Adult dogs also have higher liver storage that helps produce energy when blood sugar is low. However, immature livers can’t manufacture enough sugar to maintain some puppies through times of stress or food shortage, so tiny pups are more likely to develop hypoglycemia.

Symptoms of Hypoglycemia in Puppies

The signs of low blood sugar can be subtle. It’s important to watch out for them, especially if your puppy is a small or toy breed. Without enough sugar, a puppy’s heartbeat rate and breathing slow down, triggering a cascade of progressively serious symptoms.

Be alert for any of the following atypical behaviors and symptoms.


  • Weakness
  • Sleepiness
  • Disorientation
  • Wobbly gait or stumbling
  • Twitching, shaking, trembling, or shivering
  • Seizures
  • Unconsciousness

When the blood sugar drops, puppies can’t regulate their body temperature, so they become cold and drowsy. The lack of available sugar in the bloodstream also affects nerves, inducing clumsiness, shivering or tremors, and even full-blown seizures. Untreated, a coma may ensue, and the puppy may die if it does not receive sugar.

Causes of Hypoglycemia

Puppies can develop low blood sugar for a few reasons, but the exact cause may require veterinary assistance to identify. All of the following can cause low blood sugar and have similar symptoms:

  • Intestinal parasites that compromise digestion
  • Irregular feeding schedule or lack of food
  • Low sugar storage in liver
  • High metabolic rate
  • Portosystemic shunt (abnormal blood vessel around the liver)

Diagnosing Hypoglycemia in Puppies

A veterinarian uses multiple approaches to diagnose hypoglycemia. In addition to considering the pup's symptoms and medical history, the vet will likely perform a physical exam as well as a CBC (complete blood count), serum biochemistry profile, and urinalysis. Depending on the results of the lab work, your vet may suggest further testing to identify physical abnormalities like a portosystemic shunt.


Fortunately, when you recognize the signs of hypoglycemia in a puppy (such as stumbling or sudden sleepiness), the condition is easy to reverse at home. In almost all cases, the puppy will respond very quickly to treatment, within 10 minutes.

Getting sugar into the puppy is key because it will resolve the acute hypoglycemic episode. A highly concentrated sugar source like Karo syrup, maple syrup, or honey can work. Spoon about a teaspoon of syrup into the pup's mouth, or rub a little on the gums.

If your puppy has a seizure or falls unconscious, drip the sugar source onto the dog's lips and gums, then get to your veterinarian's office as soon as possible for further evaluation and treatment.

Even when your pup responds quickly to a sugar source, it’s a good idea to schedule a prompt veterinary exam to assess the cause and determine preventative measures to avoid future episodes of low blood sugar.

Prognosis for Puppies with Hypoglycemia

With an attentive owner that is ready to administer sugar support, a hypoglycemic puppy can recover from an acute episode very quickly. The long-term prognosis, however, can vary according to the underlying cause of the low blood sugar, and the condition may need to be managed with diet or medications for life.

How to Prevent Hypoglycemia

When your puppy has suffered from a bout of hypoglycemia, you’ll know to be alert for the signs of low blood sugar in the future. You can also take steps to prevent the problem, especially if your puppy is a high-risk pet.

  • Add two tablespoons of Karo syrup to your puppy’s water for all-day sipping. Be sure to dump it out and add fresh each day or the sugar water could grow bacteria.
  • Schedule several meals every day. Young puppies have trouble eating enough food in one sitting. A small meal several times a day helps keep the blood sugar levels normalized.
  • Keep dry food available all day for intermittent snacking. You can measure this amount to regulate how much food the puppy is eating daily. This will help prevent puppy obesity while providing healthy blood sugar levels.

Most adult dogs won’t have problems with hypoglycemia. However, playing and running too hard without rest can cause low blood sugar even in adults that are not toy breeds.

If you suspect your pet is sick, call your vet immediately. For health-related questions, always consult your veterinarian, as they have examined your pet, know the pet's health history, and can make the best recommendations for your pet.
Article Sources
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  1. Hypoglycemia in Small Breed Puppies and Young Kittens. Metropolitan Veterinary Associates.

  2. Testing for Low Blood Sugar. VCA Animal Hospitals.