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Zwolfe Long Acting IM

Important Note

Warnings
Uses
Side Effects
Precautions
Interactions
Overdose
Zwolfe Long Acting IM Uses

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 (e.g., poor nutrition, stomach/intestinal problems, infection, cancer). Serious vitamin B12 deficiency may result in anemia, stomach problems, and nerve damage.

How to use Zwolfe Long Acting IM

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 (e.g., 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 visually for particles or discoloration. If either is present, do not use the liquid. Learn how to store and discard medical supplies safely.

Zwolfe Long Acting IM Side Effects

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

Remember that your doctor has prescribed this medication because he or she 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 immediately if any of these unlikely but serious side effects occur: muscle cramps, weakness, irregular heartbeat.

People who have a rare blood disorder (polycythemia vera) may infrequently have symptoms related to this disorder while taking hydroxocobalamin. Get medical help right away if any of these rare but very serious symptoms occur: chest pain (especially with shortness of breath), weakness on one side of the body, sudden vision changes, slurred speech.

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.

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

Zwolfe Long Acting IM Precautions

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 breast-feeding.

Zwolfe Long Acting IM Interactions

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.

Some products that may interact with this drug include: drugs that may affect blood cell production (e.g., chloramphenicol, anti-cancer drugs, HIV drugs), other vitamins/nutritional supplements (especially folic acid).

Certain other drugs may interfere with laboratory tests for vitamin B12 levels, possibly causing false test results. Tell laboratory personnel and all your doctors if you take any of the following: anti-infective drugs (e.g., amoxicillin, erythromycin), methotrexate, pyrimethamine.

Zwolfe Long Acting IM Overdose

Overdose with this medication is very unlikely. However, if overdose is suspected, contact a poison control center or emergency room immediately. US residents can call their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center.

NOTES:

Do not share this medication with others.

Laboratory and/or medical tests (e.g., serum potassium levels, complete blood count, hematocrit, vitamin B12 levels) should be performed to monitor your progress or check for side effects. 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.

MISSED DOSE:

For the best possible benefit, it is important to receive each scheduled dose of this medication as directed. If you miss a dose, contact your doctor or pharmacist immediately to establish a new dosing schedule. Do not double the dose to catch up.

STORAGE:

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.

Information last revised March 2013. Copyright(c) 2013 First Databank, Inc.

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You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.

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