Trade Names:B-12 Dots- Tablets, sublingual 500 mcg
Trade Names:CaloMist- Spray, intranasal 25 mcg per 0.1 mL
Trade Names:Nascobal- Spray, intranasal 500 mcg per 0.1 mL
Trade Names:Rubesol-1000- Injection 1,000 mcg/mL
Trade Names:Twelve Resin-K- Tablets 1,000 mcg
Trade Names:Vitamin B 12- Tablets 50 mcg- Tablets 100 mcg- Tablets 500 mcg- Tablets 1,000 mcg- Tablets, sublingual 1,000 mcg- Tablets, sublingual 2,500 mcg- Tablets, sublingual 5,000 mcg- Lozenges 50 mcg- Lozenges 100 mcg- Lozenges 250 mcg- Lozenges 500 mcg
Trade Names:Vitamin B 12- Tablets, ER 1,500 mcg
Involved in protein synthesis; Vitamin B 12 is essential to growth, cell reproduction, hematopoiesis, and nucleoprotein and myelin synthesis.
T max is 1 h.
IntranasalT max is 1.25 h. C max is about 757.96 pg/mL.
OralBound to intrinsic factor during transit through the stomach; separation occurs in the presence of calcium, and vitamin B 12 enters the mucosal cells for absorption.
Distributed and stored primarily in the liver and bone marrow. In the blood, it is bound to trancobalam II.
Unbound vitamin B 12 is rapidly eliminated in the urine.
IM50% to 98% is excreted in the urine within 48 h.
Treatment of vitamin B 12 deficiency caused by inadequate utilization of vitamin B 12 ; dietary deficiency of vitamin B 12 occurring in strict vegetarians; malabsorption syndrome of various causes (eg, pernicious anemia, GI pathology, fish tapeworm infestation, malignancy of pancreas or bowel, gluten enteropathy, small bowel bacterial overgrowth, gastrectomy, concurrent folic acid deficiency); supplementation because of increased requirements (eg, associated with pregnancy, thyrotoxicosis, hemolytic anemia, hemorrhage, malignancy, hepatic and renal disease); vitamin B 12 absorption test (eg, Schilling test).
IntranasalMaintenance of vitamin B 12 concentrations after normalization with IM vitamin B 12 therapy in patients with vitamin B 12 deficiency without nervous system involvement.
NascobalMalabsorption of vitamin B 12 resulting from structural or functional damage to the stomach, where intrinsic factor is secreted, or to the ileum, where intrinsic factor facilitates vitamin B 12 absorption (eg, AIDS, HIV infection, tropical sprue); inadequate secretion of intrinsic factor resulting from lesions that destroy the gastric mucosa (eg, ingestion of corrosives, extensive neoplasia) and conditions associated with variable degree of gastric atrophy (eg, multiple sclerosis, HIV infection, iron deficiency, total gastrectomy); competition for vitamin B 12 by intestinal parasites or bacteria (eg, fish tapeworm); inadequate utilization of vitamin B 12 (eg, antimetabolites for vitamin B 12 are employed in the treatment of neoplasia).
Hypersensitivity to cobalt, vitamin B 12 , or any component of these medications.
1 spray in each nostril once daily (25 mcg per nostril; total daily dose, 50 mcg). Increase the dose to 1 spray in each nostril twice daily (total daily dose, 100 mcg) for patients who have an inadequate response to once-daily dosing.
NascobalAdultsIntranasal 1 spray (500 mcg) in 1 nostril once weekly. Administer at least 1 h before or 1 h after ingestion of a hot food or liquid.
ChildrenIntranasal Dose should be in the amount recommended by the Food and Nutrition Board, National Academy of Science-National Research Council.
Recommended Dietary AllowanceAdults and Children 14 yr of age and olderPO 2.4 mcg/day.
Children 9 to 13 yr of agePO or SL 1.8 mcg/day.
Children 4 to 8 yr of agePO or SL 1.2 mcg/day.
Children 1 to 3 yr of agePO or SL 0.9 mcg/day.
Pregnancy (14 to 50 yr of age)PO or SL 2.6 mcg/day.
Lactation (14 to 50 yr of age)PO or SL 2.8 mcg/day.
Adequate Intake for Children 7 to 12 mo0.5 mcg/day.
Adequate Intake for Children 0 to 6 mo0.4 mcg/day.
Dietary SupplementAdultsPO or SL 50 to 5,000 mcg/day.
Vitamin B 12 DeficiencyAdultsPO or SL 25 to 1,000 mcg/day.
IM or deep subcutaneous 30 mcg/day for 5 to 10 days followed by 100 to 200 mcg/mo.
Addisonian Pernicious AnemiaAdultsIM or deep subcutaneous 100 mcg/day for 6 to 7 days. If reticulocyte response occurs, give 100 mcg every other day for 7 doses, then give 100 mcg every 3 to 4 days for 2 to 3 wk. After this regimen, give 100 mcg/mo for life.
ChildrenIM or deep subcutaneous 0.5 to 3 mcg/day.
Shilling Test Flushing DoseAdultsIM 1,000 mcg (z-tract method preferred).
Store upright at 59° to 86°F. Protect from light and freezing.
Decreases hematologic effects of vitamin B 12 in patients with pernicious anemia.
Colchicine, excessive alcohol intake (more than 2 wk), para-aminosalicylic acidDecreases GI absorption of vitamin B 12 .
FoodHot foods may cause nasal secretions, resulting in loss of medication; therefore, administer intranasal dose form at least 1 h before or after ingestion of hot foods or liquids.
May invalidate vitamin B 12 diagnostic microbiological blood assays.
May mask the true diagnosis of megaloblastic anemia or folate deficiency.
Peripheral vascular disorder (1%); CHF; peripheral vascular thrombosis; pulmonary edema.
Dizziness, headache (12%); asthenia, hypersomnia, malaise, pyrexia, sinus headache (4%); paresthesia (1%).
ParenteralHeadache (11%); asthenia (4%); dizziness, nervousness (3%); incoordination (2%); abnormal gait, anxiety, hypoesthesia, paresthesia (1%).
Rash (8%).
ParenteralItching, transitory exanthema.
Nasopharyngitis, rhinorrhea (12%); nasal discomfort (8%); epistaxis, pharyngolaryngeal pain, postnasal drip (4%); rhinitis (1%).
ParenteralRhinitis (2%).
Tooth abscess (4%) glossitis, nausea (1%).
ParenteralDyspepsia (2%); nausea, nausea and vomiting, vomiting (1%); mild transient diarrhea.
Polycythemia vera.
Arthralgia (12%); back pain (4%).
ParenteralArthritis (2%); back pain, myalgia (1%).
Bronchitis (8%); asthma, cough, sinusitis (4%).
ParenteralDyspnea (1%).
Pain (8%); infection, influenza-like illness, procedural pain, scab (4%).
ParenteralGeneralized pain, infection (3%); anaphylactic shock, death, feeling of swelling of entire body.
PostmarketingAngioedema, angioedema-like reactions.
MonitorObtain all hematologic parameters, including hemacrit, reticulocyte count, and vitamin B 12 , folate, and iron levels, at the beginning of vitamin B 12 treatment. Monitor serum potassium levels during therapy. Periodically monitor serum B 12 levels to establish adequacy of therapy. Monitor vitamin B 12 concentrations and CBC 1 month after starting treatment and at 3- to 6-month intervals thereafter. Patients with declining or abnormally low vitamin B 12 concentrations despite maximal doses of intranasal treatment should be switched to IM vitamin B 12 . |
Category A ( Category C in doses that exceed the RDA, Nascobal , CaloMist , injection).
Excreted.
Safety and efficacy not established.
Use with caution, usually starting at the low end of the dosage range, because of the greater frequency of decreased hepatic, renal, or cardiac function, and concomitant diseases or other drug therapy.
Anaphylactic shock and death have been associated with parenteral use.
Patients with vitamin B 12 deficiency may require an increased dose or more frequent therapy.
Patients with vitamin B 12 deficiency may require an increased dose or more frequent therapy.
Patients with early Leber disease (hereditary optic nerve atrophy) suffered severe and rapid optic atrophy when treated with cyanocobalamin. Do not use cyanocobalamin in these patients. Infection, uremia, concurrent iron or folic acid deficiency, and drugs with bone marrow–suppressant properties may blunt the therapeutic response to cyanocobalamin.
Parenteral form contains aluminum that may be toxic, especially in patients with renal function impairment.
Injection may contain benzyl alcohol, which has been associated with fatal “gasping syndrome” in premature infants.
Could occur upon conversion of severe megaloblastic to normal erythropoiesis with vitamin B 12 .
Cyanocobalamin nasal administration has not been evaluated in patients with nasal congestion, allergic rhinitis, upper respiratory tract infections, or other nasal pathologies.
Overdosage has not been reported.
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