You can trust this content. Vet-Approved Content

Puppy Hypoglycemia: A Giant Syndrome

Low blood sugar in small puppies is common and needs to be treated right away to avoid seizures and sometimes death.

Goliath came into the hospital with hypoglycemia. Photos by: Dr. Deb Lichtenberg, VMD/Petful
Goliath came into my hospital with hypoglycemia. Photos by: Dr. Debora Lichtenberg, VMD/Petful

I like to think of myself as a youngster, but that would be fantasy.

I opened my veterinary hospital almost 25 years ago, so the youngster left the building a long time ago. My hospital is in a converted barn behind my old New England farmhouse. Truly, I live where I work.

So, over the years, I’ve had a lot of people banging on my back door in the middle of the night looking for help, usually with a very sick pet in their arms.

This week’s after-hours incident was on the brighter side.

I had just closed the hospital after a 10-hour day and was flopped over at my kitchen table. I looked out the window and saw a young woman walking away, carrying something tiny swaddled in a blanket and sobbing.

My husband ran out to greet her. “The hospital is closed,” he said, “but we will help you.”

Goliath, the Wonder Puppy

The rumpled bundle in her arms was a shaking puppy. The good news: I took a quick look at this pup and was quite sure the outcome would be positive.

My puppy emergency patient was named Goliath (although I renamed him David in my head). A 4-pound foo-foo of adorable fluff, Goliath was certainly no biblical giant on this night. Shivering but still trying to wag his tail, the pup’s vital signs were all good.

He was fighting a syndrome called hypoglycemia, but he was going to win. With a little veterinary help, the giant disease of hypoglycemia would be defeated and the little man could reclaim his name.

Juvenile Hypoglycemia

Hypoglycemia, or low blood sugar, is a syndrome common in small puppies. Toy breeds and chihuahuas are particularly susceptible.

They come in shaking with head tremors and can convulse, seize and potentially die. We must regulate their blood sugar quickly and carefully, and then monitor it until they can maintain a normal blood sugar.

Within minutes of receiving dextrose intravenously, Goliath was back to his old self.
Within minutes of receiving dextrose intravenously, Goliath was back to his old self.

Causes of Low Blood Sugar in Puppies

We don’t always know why a pup experiences low blood sugar, but any stress or illness can bring on an episode. Once corrected with proper care and nutrition, the pup should grow out of this condition.

In a healthy puppy, a hypoglycemic episode can result from an immature liver, a slight illness or loss of a few meals. But in a sick pup, there are many reasons a puppy might go into hypoglycemic shock, and the underlying cause should be identified and corrected.

Some of the culprits are:

  • Parasites
  • Viral or bacterial disease
  • Metabolic or liver abnormalities, such as a PSS (portosystemic shunt)
  • Poor neonatal nutrition
  • Hypothermia
  • Insufficient food intake
  • Dehydration

Diagnosis and Treatment

Goliath’s acute onset of head and body tremors told me to test his blood sugar first. A quick 30 test confirmed it was 36 — normal blood sugar is around 100. Puppies usually begin to go comatose and/or seize when the blood sugar goes much lower than 30.

I started Goliath on an IV drip and gave him a safe and steady supply of dextrose to bring up his blood sugar. Within a few minutes, the shaking and trembling stopped. In a few more minutes, he wanted to run around the surgery room with his IV still attached. He was a 4-pound Goliath again.

This was a great sight to behold. His human was still crying, but now they were tears of joy. Then Goliath stuck his puppy face in a bowl of food and finished it.


Ideally, puppies should be monitored in an ICU for at least 24 hours to continue the dextrose if needed, check blood sugar levels, and make sure they are eating and drinking on their own.

But Goliath’s caretaker was reluctant to do this. A new neighbor who lives directly across the street, she had brought Goliath to a low-cost clinic for a round of puppy shots, but these clinics do not offer medical care or emergency coverage.

I made a deal with her: If she made sure Goliath could be roused and would slurp up some food every 2 hours, she could monitor him at home.

In the morning, I called to discover that Goliath was now eating and tearing around the house. He soon became a registered patient of mine.

There’s nothing wrong with trying to save money at a low-cost clinic — pets are expensive. But please make a relationship with a full-service hospital when you acquire a new pet. When you need help after hours, the clinic at the back of a pet store will not answer the phone.


This pet health content was written by a veterinarian, Dr. Debora Lichtenberg, VMD. It was reviewed for accuracy by Dr. Pippa Elliott, BVMS, MRCVS, and was last updated Oct. 13, 2018.