Cyanocobalamin injection

Cyanocobalamin and the derivative hydroxo-cobalamin, given IM or deep subcutaneously, are indicated for treating vitamin B12 deficiency. Only in strict vegetarians oral preparations may be effective. Oral preparations with added intrinsic factor mostly are not reliably in patients with pernicious anemia. More than half the dose of cyanocobalamin injected is excreted in the urine within 48 hours and the therapeutic advantages of doses higher than 100 pg are questionable because of this rapid eiimination. As... 

Cyanocoba/am/n- Cyanocobalamin is rapidly absorbed from IM and subcutaneous injection sites the plasma level peaks within 1 hour. Once absorbed, it is bound to plasma proteins, stored mainly in the liver and is slowly released when needed to carry out normal cellular metabolic functions. Within 48 hours after injection of 100 to 1,000 meg of vitamin B-12, 50% to 98%... 

Vitamin B12 for parenteral injection is available as cyanocobalamin or hydroxocobalamin. Hydroxocobalamin is preferred because it is more highly protein-bound and therefore remains longer in the circulation. Initial therapy should consist of 100-1000 meg of vitamin B12 intramuscularly daily or every other day for 1-2 weeks to replenish body stores. 

In pernicious anemia, vitamin B12 should be given as intramuscular injection or high-dose oral supplements. Intramuscular injections of 100 to 1000 pg of cyanocobalamin for 5 d and 100 to 1000 pg of cyanocobalamin each month thereafter is a sufficient protocol for treating pernicious anemia (see Baik and Russell, 1999). 

Two forms of vitamin B12 are available for treatment, cyanocobalamin and hydroxocobalamin, both showing similar activity in man. Hydroxocobalamin is retained in the body more efficiently than cyanocobalamin. It disperses more slowly from the injection site (K8) and therefore a larger percentage of the dose is retained. 

In the setting of established B12 deficiency, treatment is usually by parenteral injection, with 1000 tg given daily for the first 5 days. Thereafter, cyanocobalamin (1000 tg) is given monthly by intramuscular or deep subcutaneous injection. While orally administered drug is not recommended in most patients who have a B12 deficiency due to malnutrition or achlorhydria (failure to release food-bound B12), 1000 jig oral vitamin B12 can be administered daily. A... 

Hydroxocobalamin is bound to plasma protein to a greater extent than is cyanocobalamin, with the result that there is less free to be excreted in the urine after an injection and rather lower doses at longer intervals are adequate. Thus hydroxocobalamin is preferred to cyanocobalamin, though the latter can give satisfactory results as the doses administered are much greater than are required physiologically. Cyanocobalamin remains available. 

A 42-year-old woman who had received monthly intramuscular cyanocobalamin for 4 years developed Quincke s edema. She was given hydroxocobalamin instead, each injection being preceded by 4 mg of... 

A 35-year-old woman who had received monthly intramuscular hydroxocobalamin for 6 years developed anaphylactic shock immediately after a dose. Later she was given cyanocobalamin with terfenadine 120 mg/day for 2 days before each injection. After 3 years she had not had any allergic reactions. 

Vaidyanathan S, Soni BM, Oo T, Watt JW, Sett P, Singh G. Syncope following intramuscular injection of hydroxocobalamin in a paraplegic patient indication for oral administration of cyanocobalamin in spinal cord injury patients. Spinal Cord 1999 37(2) 147-9. 

Cobalamin Concentrate, USP. Cobalamin concentrate. derived from culturc.s of Sireptomyces spp. or of other cobalamin-producing microorganism.s. contains 500 g of cobalamin per gram of concentrate. A cyanocobalamin-zinc tannate complex can be used as a repository form for the slow relea.se of cyanocobalamin when it is administered by injection. 

Vitamin Bn can be deficient due to a lack of intrinsic factor, which is a glycoprotein secreted by gastric parietal cells. A lack of intrinsic factor or a dietary deficiency of cobalamin can cause pernicious anemia and neuropsychiatric symptoms. The only known treatment lor intrinsic factor deficiency (vitamin Bn deficiency) is intramuscular injection of cyanocobalamin throughout the patient s life. 

In regard to vitamin B12 deficiency, the average wholesale price for oral cyanocobalamin tablets and the IM injections is inexpensive. However, significant costs are added to the parenteral route, including the cost of a physician or nurse s visit for injection or home health visit. Additionally, many elderly patients may have difficulties attending additional clinic appointments due to transportation difficulties. An IM injection of cyanocobalamin costs between 10 and 25 for an in-office visit and between 60 and 100 for administration via home health care provider. A 90-day supply of 1-mg oral tablets can be purchased over the counter for approximately 5. The disadvantage of the nasal gel is its cost as compared to the oral or parenteral route, with a 2-month supply costing approximately 60. 

Cyanocobalamin[ Co] capsules Cyanocobalamin[ Co] capsules Cyanocobalamin[ Co] solution Cyanocobalamin[ Co] solution 2-Fluoro-2-deoxy-D-glucose[ F] injection... 

Practically insol in water. On reconstitution forms a colloidal suspension, incompatible with iron salts. After intra -muscular injection of 500-, a high cyanocobalamin serum level persists for 28 days., ... 

VITAMIN Bj2 therapy Vitamin B is available for injection or oral administration combinations with other vitamins and minerals also can be given orally or parenterally. The choice of a preparation always depends on the cause of the deficiency. Although oral preparations may be used to supplement deficient diets, they are of limited value in the treatment of patients with deficiency of intrinsic factor or deal disease. Even though small amounts of vitamin may be absorbed by simple diffusion, the oral route of administration cannot be rehed upon for effective therapy in the patient with a marked deficiency of vitamin Bj and abnormal hematopoiesis or neurological deficits. Therefore, the treatment of choice for vitamin Bj -deficiency is cyanocobalamin administered by intramuscular or subcutaneous injection. 

Vitamin Bj should be given prophylactically only when there is a reasonable probability that a deficiency exists or wdl exist. Dietary deficiency in the strict vegetarian, the predictable malabsorption of vitamin Bj in patients who have had a gastrectomy, and certain diseases of the small intestine constitute such indications. When GI function is normal, an oral prophylactic supplement of vitamins and minerals, including vitamin Bj, may be indicated. Otherwise, the patient should receive monthly injections of cyanocobalamin. 

Vitamin deficiency occurs when there is malabsorption because of a lack of intrinsic factor (pernicious anttemia). following gastrectomy (no intrinsic factor), or in various small bowel diseases, where absorption is impaired. Because the disease is nearly always cau.sed by malabsorption. oral vitamin administration is of little value, and replacement Iherapy, usually for life, involves injections of vitamin (left). Hydroxocobulamin is the form of choice for ilierapy because it is retained in Ihe body longer than cyanocobalamin (cyanocobalamin is bound less to plasma proteins and Ls more rapidly excreted in urine). 

Supplements. Cyanocobalamin (readily converted in the body to the bioavailable forms 5-deoxy-adenosyl and methylcobalamin) is the principal form of vitamin B,2 used in supplements but methylcobalamin is also available. Cyanocobalamin is available by prescription in an injectable form and as a nasal gel for the treatment of pernicious anemia. Over the counter preparations containing cyanocobalamin include multivitamin, vitamin B-complex, and vitamin B,2 supplements. ... 

Cyanocobalamin (vitamin B12), injected into a muscle, travels to the bone-marrow and is accumulated there after a dilution of 10 -fold in the body fluids. Even a microgram, injected in this way, is enough to cause new reticulocytes to form in the marrow of a patient suffering from pernicious anaemia. The process of distribution has been followed with Co. 

Another possible explanation of the observed reactions are the additives in pharmaceutical preparations. Thus Lagerholm et al. (1958) reported a case of hypersensitivity to benzyl alcohol added as a preservative to vitamin B 2 preparations, resulting in urticaria after injection, Hovding (1968), however, was not able to demonstrate a positive skin reaction either with benzyl alcohol or with cobalt chloride. However, skin tests with commercial brands of cyanocobalamin and hydroxocobalamin as well as with purified cyanocabalamin and hydroxocobalamin were positive. Malten (1975) reports a flare reaction in a woman due to the third injection of 250 pg vitamin B12. Prick and patch tests, however, remained negative. A recent short review of reactions after administration of vitamin Bj2 preparations was published by Meuwissen (1978). An extensive review covering the literature up to 1975 was presented by Faivre et al. (1975). The authors conclude that, despite the widespread use of vitamin B12 preparations, cases of accidents after vitamin Bi2 administration are very rare, but nevertheless are a potential risk. Therefore, skin and immunologic tests should be made prior to administration and especially parenteral application of the vitamin. The authors do not make an explicit statement as to a definite allergic mechanism of the observed phenomena. 

Horwitt MK (1972) Vitamin B2 pharmacology and toxicology. Vitamins 5 85-87 Hovding G (1968) Anaphylactic reaction after injection of vitamin Bi2- Br Med J 610 102 James J, Warin RP (1971) Sensitivity to cyanocobalamin and hydroxocobalamin. Br Med J 5756 262... 

Some forms of MMA may be responsive to vitamin Bjj. Responsiveness can be determined by administration of 1.0 mg hydroxocobalamin (IM or IV) for 5 days. A reduction in serum methylmalonic acid concentrations of 50 % or greater suggests responsiveness [14]. For those with cobalamin-responsive forms of MMA, intramuscular (IM) hydroxocobalamin injections of 1.0-2.0 mg are often administered daily. A decreased frequency of IM injections or use of oral supplements may be appropriate for older individuals. The hydroxocobalamin form rather than the standard cyanocobalamin form must be used [15]. 

---