Cyanocobalamin (B12 or Cobalamin)

What is cyanocobalamin?

Cyanocobalamin (vitamin B12 or cobalamin) is a vitamin supplement used to treat systemic deficiencies of vitamin B12 due to metabolic or genetic disorders. It has been used in the treatment of some forms of anemia, cobalt deficiency, exocrine pancreatic insufficiency, chronic enteropathies, and other conditions.

The U.S. Food and Drug Administration (FDA) does not review non-drug health products (e.g., herbals, nutraceuticals, shampoos, and other supplements) for safety or effectiveness before they are sold to the public. Manufacturers of non-drug health products must ensure their products are safe and labeled accurately. The FDA requires that these non-pharmaceuticals contain a disclaimer that says, “This product is not intended to diagnose, treat, cure or prevent any disease.” Health Canada licenses “veterinary health products” after reviewing safety, efficacy, and manufacturing information provided by the manufacturer. These products are not tested by Health Canada.

Your veterinarian is the best source of information about the safety of non-drug health products in pets. Just because a product is natural does not mean it is safe. All medicines and medicinal plants are potentially toxic if used inappropriately or given at high doses. Supplements can also have side effects, like pharmaceuticals. Few supplements and herbs have been subjected to rigorous scientific trials to determine their efficacy. 

Although the information in this handout may be helpful, it also may be incomplete and may not represent the full range of effects the supplement could have on your pet.

How is cyanocobalamin given?

• Cyanocobalamin is given by mouth in the form of an oral tablet or is given under the skin in the form of an injectable solution.
• A member of your veterinary team can show you how to properly inject this supplement.
• Follow your veterinarian’s instructions on administering this supplement carefully and give it for the entire time prescribed by your veterinarian, even if your pet is feeling better.

It can take several weeks before the full effects of this supplement are noted.

What if I miss giving my pet the supplement?

If you miss a dose, give it as soon as you remember and start a new weekly or monthly dosing schedule. For example, if you forgot to give your pet their monthly dose on June 1 and remember on June 18, give the dose on June 18 and start a new monthly schedule. You will give your pet the next dose on July 18. Do not give your pet two doses at once. Contact your veterinarian if you are concerned about a missed dose.

Are there any potential side effects?

This is a longer-acting supplement that appears to be well tolerated in animals. The injection may sting but typically resolves quickly.

Serious adverse reactions may occur. If any of the following signs develop, stop giving and contact your veterinarian immediately:

• An allergic reaction such as irregular breathing, rash, fever, puffiness and swelling around the face

Drug sensitivities can develop over time with repeated exposure. Your pet may have no reaction after the first few doses, but may develop a sensitivity later. It is important to watch for signs of an allergic reaction over the entire course of treatment. Other side effects may occur. If you notice anything unusual, contact your veterinarian immediately. The effects of this supplement may last for a few days.

Are there any risk factors for this supplement?

No risk factors are documented for injectable or oral use of cyanocobalamin in pets. It is likely safe to use in pregnant animals and is safe to use in nursing mothers and young animals.

Are there any drug interactions I should be aware of?

The following medications should be used with caution when given with cyanocobalamin:

• Chloramphenicol
• Omeprazole, pantoprazole

Vitamins, herbal therapies, and supplements have the potential to interact with each other, as well as with prescription and over-the-counter medications. Be sure to tell your veterinarian about any medications (including all vitamins, supplements, or herbal therapies) that your pet is taking before starting any new treatment.

Is any monitoring needed with this supplement?

• Your veterinarian will let you know when and how they want to reassess your pet to ensure the supplement is working and not causing side effects.
• Your veterinarian may recommend a baseline blood panel before starting treatment with cyanocobalamin and will recheck once treatment has begun.
• Follow your veterinarian’s recommendations on monitoring blood work timelines.
• At home, monitor for any abnormal changes. If any occur, discontinue the supplement and contact your veterinarian.

How do I store cyanocobalamin?

• Store tablets in tight containers at room temperature and protected from light.
• Cyanocobalamin injectable should be stored below 104°F (40°C) and protected from light and freezing.
• Keep the container out of reach of children and pets. 

What should I do in case of emergency?

If you suspect an overdose or an adverse reaction to the supplement, call your veterinary office immediately. If they are not available, follow their directions in contacting an emergency facility. Be prepared to provide information about the product and your pet's weight and symptoms. Report any adverse effects to the FDA or Health Canada.