Vitamin B12 Injection

The active ingredient in vitamin B12 injections is cyanocobalamin. Cyanocobalamin is the inactive form of vitamin B12 and must be metabolized in the body to the active form. Vitamin B12 acts as a cofactor and is involved in DNA synthesis, nervous system function, energy levels, and the formation of red blood cells.

Follow all directions given to you by your doctor and read all documents provided, including the full Prescribing Information, FDA-Approved Product Labeling, Instructions for Use, and Medication Guide, before using vitamin B12 injections. However, the following is a synopsis of the general guidelines for the use of vitamin B12 injections:

• Vitamin B12 shots are available as cyanocobalamin and hydroxocobalamin. The FDA-approved cyanocobalamin dose for adults is 100 mcg daily for 7 days, and then 100 mcg every other day for 14 days or every 3 to 4 days for weeks. Once your vitamin B12 levels are in the normal range, it’s recommended to continue 100 mcg injections once a month. There are other effective dosing schedules, so it is best to follow what your healthcare provider has told you.
• Vitamin B12 injections are given intramuscularly or subcutaneously by your healthcare provider. Your healthcare provider may also teach you how to inject yourself.
• Your healthcare provider may monitor your vitamin B12 levels with blood tests to ensure your levels are improving.
• Vitamin B12 deficiency may occur due to poor dietary intake of vitamin B12, poor absorption, or autoimmune diseases like Crohn’s disease. Vegetarian and vegan diets often have low amounts of vitamin B12, as vitamin B12 is mostly found in animal products.

The most common side effects of vitamin B12 injections include:

• Injection-site reactions.
• Nausea.
• Vomiting.
• Headache.
• Diarrhea.

Some individuals may experience serious side effects while using vitamin B12 injections. These side effects may require immediate medical attention. If you experience any of the following, contact your healthcare provider or seek emergency medical help:

• Allergic reaction. Symptoms include hives, trouble breathing, and swelling of the face, lips, or tongue.
• Heart failure. Symptoms include sudden weight gain or shortness of breath.
• Hypokalemia (low levels of potassium). Symptoms include muscle cramps, weakness, and irregular heartbeat.

These are not all of the possible side effects of vitamin B12 injections. You should always seek medical advice from your healthcare provider for any questions or concerns about your medical condition or treatment. Read all patient information, medication guides, or drug information sheets that come with this medication. You can also report adverse effects to the Food and Drug Administration at www.fda.gov/medwatch or 1-800-FDA-1088.

Before starting vitamin B12 injections, it is crucial to discuss any existing health conditions with your healthcare provider. You should be sure that your healthcare provider is aware of all your medical conditions, or whether any of the following apply:

• Kidney disease.
• Gout.
• Leber’s disease.
• Megaloblastic anemia.
• Iron or folic acid deficiencies.
• Allergic reaction to medications, foods, dyes, or preservatives.
• You are taking oral vitamin B12 supplements.

Allergic reactions to any cobalt or cyanocobalamin.

Vitamin B12 injections work within hours of taking them; however, it may take weeks to see positive effects.

When vitamin B12 injections are taken with other prescription drugs, over-the-counter medications, vitamins, and supplements, it may change how they work or increase the frequency or severity of side effects. Make sure that you tell your healthcare professional about anything that you are taking to avoid any negative drug interactions, including:

• Vitamin C.
• Potassium supplements.
• Folic acid.
• Alcohol.
• Metformin.

Vitamin B12 injectable cyanocobalamin is available in 1 mL, 10 mL, and 30 mL vials that contain 1000 mcg per mL.

Store vitamin B12 injections at room temperature, away from children and pets. Do not freeze.

Vitamin B12 injections (cyanocobalamin) are generic, so multiple pharmaceutical companies manufacture them.

Vitamin B12 injections (cyanocobalamin) are the generic version.

Do not stop taking vitamin B12 injections without consulting your healthcare professional. This is because your vitamin B12 deficiency and levels may worsen.

Vitamin B12 injections are likely safe in pregnancy when used under the supervision of a healthcare professional and when it’s used to treat vitamin B12 deficiency. The daily recommended dietary allowance (RDA) of vitamin B12 in pregnancy is 2.6 mcg. Talk to your doctor if you are already pregnant or if you have any plans to become pregnant. They will know or recommend what is best for you.

Vitamin B12 injections are likely safe in breastfeeding when used under the supervision of a healthcare professional. The recommended dietary allowance (RDA) of vitamin B12 while breastfeeding is 2.8 mcg. Talk to your doctor if you are already breastfeeding or if you have any plans to breastfeed. They will know or recommend what is best for you.