Hydroxocobalamin is a man-made injectable form of vitamin B12 used to treat low levels (deficiency) of this vitamin. Vitamin B12 helps your body use fat and carbohydrates for energy and make new protein. It is also important for normal blood, cells, and nerves. Most people get enough vitamin B12 in their diet, but a deficiency may occur in certain health conditions (such as poor nutrition, stomach/intestinal problems, infection, cancer). Serious vitamin B12 deficiency may result in anemia, stomach problems, and nerve damage.

This medication is given by injection into a muscle as directed by your doctor. Dosage is based on your medical condition and response to treatment. Injections may be given daily when you first start treatment. Certain medical conditions (such as pernicious anemia) may require you to continue receiving injections every month.

If you are giving this medication to yourself at home, learn all preparation and usage instructions from your health care professional. Before using, check this product for particles or discoloration. If either is present, do not use the liquid. Learn how to store and discard medical supplies safely.

Pain at the injection site, mild diarrhea, itching, or a feeling of swelling all over the body may occur. If any of these effects last or get worse, tell your doctor or pharmacist promptly.

Remember that this medication has been prescribed because 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.

This medication may cause low potassium levels in the blood (hypokalemia). Tell your doctor right away if any of these serious side effects occur:

• muscle cramps
• weakness
• irregular heartbeat

People who have a rare blood disorder (polycythemia vera) may rarely have symptoms related to this disorder while taking hydroxocobalamin. Get medical help right away if any of these very serious symptoms occur:

• chest pain (especially with shortness of breath)
• weakness on one side of the body
• sudden vision changes
• trouble speaking

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.

Before using hydroxocobalamin, tell your doctor or pharmacist if you are allergic to it; 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.

Before using this medication, tell your doctor or pharmacist your medical history, especially of:

• low potassium blood levels (hypokalemia)
• gout
• a certain blood disorder (polycythemia vera)
• a certain eye disease (Leber's disease)
• other vitamin/mineral deficiencies (especially folic acid and iron)

During pregnancy, this medication should be used only when clearly needed. Discuss the risks and benefits with your doctor.

Based on information from related drugs, this medication may pass into breast milk. Consult your doctor before breastfeeding.

Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.

Overdose with this medication is very unlikely. However, if someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call 1-800-222-1222. Canada residents can call 1-844-764-7669.

Do not share this medication with others.

Lab and/or medical tests (such as blood potassium levels, complete blood count, hematocrit, vitamin B12 levels) should be done while you are using this medication. Keep all medical and lab appointments. Consult your doctor for more details.

This product is not a substitute for a proper diet. Remember that it is best to get your vitamins from healthy foods. Vitamin B12 is commonly found in many foods from animals, especially liver, kidney, fish and shellfish, meat, and dairy foods.

It is important to get each dose of this medication as scheduled. If you miss a dose, ask your doctor or pharmacist right away for a new dosing schedule. Do not double the dose to catch up.

Consult the product instructions and your pharmacist for storage details. Keep all medications away from children and pets.

Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company.