In puppies, large amounts of calories are necessary to meet the energy demands for growth and development. This means that lots of glucose are necessary for puppies compared to adults. Toy and small breed puppies who are younger than four months of age are at great risk of becoming hypoglycemic if they do not eat several small meals or snacks throughout the day. For these small pups, your vet or breeder might discuss the use of Nutri-Cal or Karo syrup with you. These are products that can be temporarily used if your pup isn’t eating enough.
When there is not enough glucose available to perform certain functions, the liver will release a stored form of glucose calledglycogen. This compound can be broken down into glucose. If the liver becomes diseased due to severe inflammation, infection, a liver shunt, or cancer, it may negatively impact glycogen levels. This means that dogs who are fasted and not receiving glucose through diet will have hypoglycemia. There is also an inherited disorder called glycogen storage disease which is where there is too much glycogen but not enough of the enzyme available to break it down into glucose.
When certain toxins are ingested such as xylitol (the artificial sweetening ingredient that is found in chewing gum), it will cause the release ofinsulin from the pancreas. Insulin is a hormone that helps to turn glucose into energy and helps to store the rest of it for later use. When too much insulin is present, it will cause hypoglycemia. Accidental insulin overdoses in diabetic dogs will have the same effect, and a specific type of pancreatic tumor called aninsulinoma also results in too-high levels of insulin being released into the blood.
For nursing moms, it is possible to develop hypoglycemia because the demand for glucose is very high when producing milk for puppies, especially if the litter size is greater than four puppies. And in a condition called Addison’s disease, where there are low levels of cortisol, hypoglycemia is a possibility.