Are Vitamin B12 Shots the Same for Dogs as for Humans?

A dog lacking vitamin B12 will lose weight and may refuse to eat.
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Cobalamin, or vitamin B12, supports several important functions in your dog's body, including brain and gastrointestinal tract functioning. In most dogs, a vitamin B12 deficiency usually results from an underlying medical condition that inhibits absorption of the vitamin. Such diseases include exocrine pancreatic insufficiency and small intestinal bacterial overgrowth. The most common form of injectable vitamin B12 is cyanocobalamin, and it's used in humans and in dogs.

Human B12 Injections

Injections of vitamin B12 are unnecessary for most humans, who retain the ability to absorb necessary vitamin B12 from food through the intestinal tract. Most people who take vitamin B12 do so for its various proved and unproved health benefits -- though people with pernicious anemia may need them. Humans typically receive the vitamin B12 injection in either the buttock or thigh muscle on a weekly basis.

Injectable B12 for Dogs

Like humans, dogs also receive injections of cyanocobalamin, with the dosage based upon body weight. The injections may be given subcutaneously -- beneath the skin -- or intramuscularly, typically in the thigh of the hind leg. Unlike humans, if a dog suffers from a disease that inhibits his vitamin B12 absorption, the only way he will attain sufficient levels of vitamin B12 is through the administration of injections. A normal course of treatment would include weekly vitamin B12 injections for 6 weeks, followed by one shot monthly to maintain healthy vitamin B12 levels. Do not administer anything to your dog without your vet's oversight.