Cyanocobalamin

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Precautions

Before taking cyanocobalamin, tell your doctor or pharmacist if you are allergic to it; or to any form of vitamin B12; or to cobalt; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.

If you have any of the following health problems, consult your doctor or pharmacist before using this medication: a certain eye disease (Leber's optic neuropathy), a certain blood disorder (polycythemia vera), gout, iron or folic acid deficiency anemia, low potassium blood levels (hypokalemia).

Cyanocobalamin taken by mouth should only be used if your body can properly absorb it. You may need a form of vitamin B12 that is injected or inhaled in the nose if you have any of the following health problems: pernicious anemia, food absorption problems, stomach/intestinal surgery (such as gastric bypass or bowel resection), stomach/intestinal disease (such as Crohn's disease, colitis, diverticulitis, pancreatic insufficiency), irradiation of the small bowel.

Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).

Cyanocobalamin is safe to use during pregnancy when taken in recommended doses. Higher doses should be used only when clearly needed. Discuss the risks and benefits with your doctor.

Cyanocobalamin passes into breast milk and is unlikely to harm a nursing infant when used in recommended doses. Consult your doctor before breastfeeding.

Side Effects

This product usually has no side effects. If you have any unusual effects, contact your doctor or pharmacist promptly.

If your doctor has directed you to use this medication, remember that your doctor has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

If you have severe anemia, this medication may rarely cause low potassium levels in the blood (hypokalemia) as your body makes new red blood cells. Tell your doctor right away if any of these serious side effects occur: muscle cramps, weakness, irregular heartbeat.

A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

In the US -

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch.

In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.

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Drug information is selected from data included with permission and copyrighted by First DataBank, Inc. This is a summary and does not contain all possible information about this product. For complete information about this product or your specific health needs, ask your healthcare professional. Always seek the advice of your healthcare professional if you have any questions about this product or your medical condition. This information is not intended as individual medical advice and does not substitute for the knowledge and judgment of your healthcare professional. This information does not contain any assurances that this product is safe, effective or appropriate for you.

This information is intended only for residents of the United States. Products sold under the same brand names in other countries may contain different ingredients.

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Information expires December 2025.