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What is the most important information I should know about cyanocobalamin?

You should not use this medication if you are allergic to cobalt, or if you have Leber’s disease. Cyanocobalamin can lead to optic nerve damage (and possibly blindness) in people with Leber’s disease.

To treat pernicious anemia, you will have to use this medication on a regular basis for the rest of your life. Not using the medication can lead to irreversible nerve damage in your spinal cord.

Pernicious anemia is also treated with folic acid to help maintain red blood cells. However, folic acid will not treat Vitamin B12 deficiency and will not prevent possible damage to the spinal cord. Take all of your medications as directed.

Your dose needs may change if you become pregnant, if you breast-feed, or if you eat a vegetarian diet. Tell your doctor about any changes in your diet or medical condition.

Warning

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

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What is cyanocobalamin?

Cyanocobalamin is a man-made form of vitamin B12. Vitamin B12 is important for growth, cell reproduction, blood formation, and protein and tissue synthesis.

Cyanocobalamin is used to treat vitamin B12 deficiency in people with pernicious anemia and other conditions.

Cyanocobalamin may also be used for purposes other than those listed in this medication guide.

Precautions

You should not use this medication if you are allergic to cobalt, or if you have Leber’s disease. Cyanocobalamin can lead to optic nerve damage (and possibly blindness) in people with Leber’s disease.

If you have any of these other conditions, you may need a dose adjustment or special tests to safely take oral cyanocobalamin:

  • any type of infection;
  • iron or folic acid deficiency;
  • kidney or liver disease; or
  • if you are receiving any medication or treatment that affects bone marrow.

FDA pregnancy category C. It is not known whether cyanocobalamin can harm an unborn baby. Before taking this medication, tell your doctor if you are pregnant or plan to become pregnant during treatment.

Cyanocobalamin passes into breast milk, but it is not known whether cyanocobalamin could harm a nursing baby. Do not use this medication without telling your doctor if you are breast-feeding a baby.

Avoid drinking large amounts of alcohol while you are being treated with cyanocobalamin.

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Instructions

Seek emergency medical attention if you think you have used too much of this medicine. An overdose of cyanocobalamin is not likely to cause life-threatening symptoms.

Take the missed dose as soon as you remember. If it is almost time for your next dose, wait until then to take the medicine and skip the missed dose. Do not take extra medicine to make up the missed dose.

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Side Effects

Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.

Call your doctor at once if you have a serious side effect such as:

  • chest pain;
  • feeling short of breath, even with mild exertion;
  • swelling, rapid weight gain; or
  • unusual warmth, redness, or pain in an arm or leg.

Less serious side effects may include:

  • headache, dizziness, weakness;
  • nausea, upset stomach, diarrhea;
  • numbness or tingling;
  • fever;
  • joint pain;
  • swollen tongue;
  • swelling; or
  • itching or rash.

This is not a complete list of side effects and others may occur. Tell your doctor about any unusual or bothersome side effect. You may report side effects to FDA at 1-800-FDA-1088.

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Interactions

Before taking cyanocobalamin, tell your doctor if you are taking any of the following medications:

  • antibiotics;
  • methotrexate (Rheumatrex);
  • pyrimethamine (Daraprim);
  • colchicine; or
  • if you drank a lot of alcohol within the past 2 weeks.

This list is not complete and there may be other drugs that can interact with cyanocobalamin. Tell your doctor about all your prescription and over-the-counter medications, vitamins, minerals, herbal products, and drugs prescribed by other doctors. Do not start a new medication without telling your doctor.

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Disclaimer

Every effort has been made to ensure that the information provided by Cerner Multum, Inc. ('Multum') is accurate, up-to-date, and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. Multum information has been compiled for use by healthcare practitioners and consumers in the United States and therefore Multum does not warrant that uses outside of the United States are appropriate, unless specifically indicated otherwise. Multum's drug information does not endorse drugs, diagnose patients or recommend therapy. Multum's drug information is an informational resource designed to assist licensed healthcare practitioners in caring for their patients and/or to serve consumers viewing this service as a supplement to, and not a substitute for, the expertise, skill, knowledge and judgment of healthcare practitioners. The absence of a warning for a given drug or drug combination in no way should be construed to indicate that the drug or drug combination is safe, effective or appropriate for any given patient. Multum does not assume any responsibility for any aspect of healthcare administered with the aid of information Multum provides. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the drugs you are taking, check with your doctor, nurse or pharmacist.

Copyright 1996-2004 Cerner Multum, Inc. Version 2.05. Revision date 8/23/04