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Vitamin B12 (Systemic)

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Vitamin B12 (Systemic)

US Brand Names

• Alphamin

• Cobex

• Cobolin-M

• Crystamine

• Crysti-12

• Cyanoject

• Cyomin

• Hydrobexan

• Hydro-Cobex

• Hydro-Crysti-12

• Hydroxy-Cobal

• LA-12

• Neuroforte-R

• Nascobal

• Primabalt

• Rubramin PC

• Shovite

• Vibal

• Vibal LA

• Vitabee 12

Canadian Brand Names

• Anacobin

• Bedoz


Vitamins (VYE-ta-mins) are compounds that you must have for growth and health. They are needed in small amounts only and are usually available in the foods that you eat. Vitamin B12is necessary for healthy blood. Cyanocobalamin and hydroxocobalamin are man-made forms of vitamin B12.

Some people have a medical problem called pernicious anemia in which vitamin B12is not absorbed from the intestine. Others may have a badly diseased intestine or have had a large part of their stomach or intestine removed, so that vitamin B12cannot be absorbed. These people need to receive vitamin B12by injection.

Some conditions may increase your need for vitamin B12. These include:

    • Alcoholism

    • Anemia, hemolytic

    • Fever (continuing)

    • Genetic disorders such as homocystinuria and/or methylmalonic aciduria

    • Intestine diseases

    • Infections (continuing or chronic)

    • Kidney disease

    • Liver disease

    • Pancreas disease

    • Stomach disease

    • Stress (continuing)

    • Thyroid disease

    • Worm infections

In addition, persons that are strict vegetarians or have macrobiotic diets may need vitamin B12supplements.

Increased need for vitamin B12should be determined by your health care professional.

Lack of vitamin B12may lead to anemia (weak blood), stomach problems, and nerve damage. Your health care professional may treat this by prescribing vitamin B12for you.

Claims that vitamin B12is effective for treatment of various conditions such as aging, allergies, eye problems, slow growth, poor appetite or malnutrition, skin problems, tiredness, mental problems, sterility, thyroid disease, and nerve diseases have not been proven. Many of these treatments involve large and expensive amounts of vitamins.

Injectable vitamin B12is given by or under the supervision of a health care professional. Some strengths of oral vitamin B12are available only with your health care professional's prescription. Others are available without a prescription.

Vitamin B12is available in the following dosage forms:


    • Cyanocobalamin

      o Nasal gel (U.S.)


    • Cyanocobalamin

      o Extended-release tablets (U.S.)

      o Tablets (U.S. and Canada)


    • Cyanocobalamin

      o Injection (U.S. and Canada)

    • Hydroxocobalamin

      o Injection (U.S.)

For good health, it is important that you eat a balanced and varied diet. Follow carefully any diet program your health care professional may recommend. For your specific dietary vitamin and/or mineral needs, ask your health care professional for a list of appropriate foods. If you think that you are not getting enough vitamins and/or minerals in your diet, you may choose to take a dietary supplement.

Vitamin B12is found in various foods, including fish, egg yolk, milk, and fermented cheeses. It is not found in any vegetables. Ordinary cooking probably does not destroy the vitamin B12in food.

Vitamins alone will not take the place of a good diet and will not provide energy. Your body also needs other substances found in food, such as protein, minerals, carbohydrates, and fat. Vitamins themselves often cannot work without the presence of other foods.

The daily amount of vitamin B12needed is defined in several different ways.

    For U.S.

    • Recommended Dietary Allowances (RDAs) are the amount of vitamins and minerals needed to provide for adequate nutrition in most healthy persons. RDAs for a given nutrient may vary depending on a person's age, sex, and physical condition (e.g., pregnancy).

    • Daily Values (DVs) are used on food and dietary supplement labels to indicate the percent of the recommended daily amount of each nutrient that a serving provides. DV replaces the previous designation of United States Recommended Daily Allowances (USRDAs).

    For Canada

    • Recommended Nutrient Intakes (RNIs) are used to determine the amounts of vitamins, minerals, and protein needed to provide adequate nutrition and lessen the risk of chronic disease.

Normal daily recommended intakes in micrograms (mcg) for vitamin B12are generally defined as follows:PersonsU.S. (mcg) Canada(mcg)Infants and childrenBirth to 3 years of age0.3-0.70.3-0.44 to 6 years of age10.57 to 10 years of age1.40.8-1Adolescent and adult males21-2Adolescent and adult females21-2Pregnant females2.22-3Breast-feeding females2.61.5-2.5

Before Using This Dietary Supplement

If you are taking this dietary supplement without a prescription, carefully read and follow any precautions on the label. For vitamin B12, the following should be considered:


Tell your health care professional if you have ever had any unusual or allergic reaction to vitamin B12. Also, tell your health care professional if you are allergic to any other substances, such as foods, preservatives, or dyes.


It is especially important that you are receiving enough vitamins when you become pregnant and that you continue to receive the right amount of vitamins throughout your pregnancy. Healthy fetal growth and development depend on a steady supply of nutrients from mother to fetus. However, taking large amounts of a dietary supplement in pregnancy may be harmful to the mother and/or fetus and should be avoided.

You may need vitamin B12supplements if you are a strict vegetarian (vegan-vegetarian). Too little vitamin B12can cause harmful effects such as anemia or nervous system injury.


It is especially important that you receive the right amounts of vitamins so that your baby will also get the vitamins needed to grow properly. If you are a strict vegetarian, your baby may not be getting the vitamin B12needed. However, taking large amounts of a dietary supplement while breast-feeding may be harmful to the mother and/or baby and should be avoided.


Problems in children have not been reported with intake of normal daily recommended amounts.

Older adults

Problems in older adults have not been reported with intake of normal daily recommended amounts.

Other medicines

Medicines or other dietary supplements

Although certain medicines or dietary supplements should not be used together at all, in other cases they may be used together even if an interaction might occur. In these cases, your health care professional may want to change the dose, or other precautions may be necessary. Tell your health care professional if you are taking any other dietary supplement or any prescription or nonprescription (over-the-counter [OTC]) medicine.

Other medical problems

The presence of other medical problems may affect the use of vitamin B12. Make sure you tell your health care professional if you have any other medical problems, especially:

    • Leber's disease (an eye disease)-Vitamin B12may make this condition worse

Proper Use of This Dietary Supplement


If you are taking vitamin B12intranasal gel:

    • Take it at least one hour before or one hour after hot foods or liquids .

    • Check with your doctor for follow-up blood tests every 3 to 6 months .

The amount of vitamin B12needed to meet normal daily recommended intakes will be different for different individuals. The following information includes only the average amounts of vitamin B12.

    • For nasal dosage form (intranasal gel):

      o To prevent deficiency, you are given this dosage form only if you have received vitamin B12by injection into the muscle and are in remission state.

        Adults-500 mcg (0.5 mg) into the nostrils once a week.

    • For oral dosage form (tablets or extended-release tablets):

      o To prevent deficiency, the amount taken by mouth is based on normal daily recommended intakes:

        For the U.S.

        Adults and teenagers-2 micrograms (mcg) per day.

        Pregnant females-2.2 mcg per day.

        Breast-feeding females-2.6 mcg per day.

        Children 7 to 10 years of age-1.4 mcg per day.

        Children 4 to 6 years of age-1 mcg per day.

        Children birth to 3 years of age-0.3 to 0.7 mcg per day.

        For Canada

        Adults and teenagers-1 to 2 mcg per day.

        Pregnant females-2 to 3 mcg per day.

        Breast-feeding females-1.5 to 2.5 mcg per day.

        Children 7 to 10 years of age-0.8 to 1 mcg per day.

        Children 4 to 6 years of age-0.5 mcg per day.

        Children birth to 3 years of age-0.3 to 0.4 mcg per day.

      o To treat deficiency:

        Adults, teenagers, and children-Treatment dose is determined by prescriber for each individual based on the severity of deficiency.

For patients receiving vitamin B12by injection for pernicious anemia or if part of the stomach or intestine has been removed :

    • You will have to receive treatment for the rest of your life. You must continue to receive vitamin B12even if you feel well, in order to prevent future problems.

Missed dose

If you miss taking a vitamin for one or more days there is no cause for concern, since it takes some time for your body to become seriously low in vitamins. However, if your health care professional has recommended that you take this vitamin, try to remember to take it as directed.


To store this dietary supplement:

    • Keep out of the reach of children.

    • Store away from heat and direct light.

    • Do not store in the bathroom, near the kitchen sink, or in other damp places. Heat or moisture may cause the dietary supplement to break down.

    • Do not keep outdated dietary supplement or those no longer needed. Be sure that any discarded dietary supplement is out of the reach of children.

Side Effects of This Dietary Supplement

Along with its needed effects, a dietary supplement may cause some unwanted effects. Cyanocobalamin or hydroxocobalamin does not usually cause any side effects.

However, check with your health care professional immediately if any of the following side effects occur:


soon after receiving injection onlySkin rash or itching; wheezing.

Check with your health care professional as soon as possible if either of the following side effects continues or is bothersome:

Less common

Diarrhea; itching of skin.

Other side effects not listed above may also occur in some individuals. If you notice any other effects, check with your health care professional.


This information applies to the following:

1. Cyanocobalamin (sye-an-oh-koe-BAL-a-min)
2. Hydroxocobalamin (hye-drox-oh-koe-BAL-a-min)
June 23, 2000

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