Multivitamin

The vitamin B12 content of a multivitamin tablet is determined by dissolving ten tablets in water. The dissolved tablets are transferred to a 100-mL volumetric flask and diluted to volume. A 50.00-mL portion is removed and treated with 0.500 mg of radioactive vitamin B12 having an activity of 572 cpm. After homogenization, the vitamin B12 in the sample is isolated and purified, producing 18.6 mg with an activity of 361 cpm. Calculate the average concentration of vitamin B12 in the tablet (in milligrams per tablet). 

Fig. 2. International fmit juice and drink consumption (12) I orange, apple, U grape-fmit, VA grape, and multivitamin or blends. Values ate in...

A major pharmaceutical use of poly(oxyethylene) sorbitan fatty acid esters is in the solubilization of the oil-soluble vitamins A and D. In this way, multivitamin preparations can be made which combine both water- and oil-soluble vitamins in a palatable form. 

The biotin market is divided between agricultural and human use, with —90% of biotin used in the animal health care market and —10% for the human nutritional market. The major producers of biotin are Hoffmann-La Roche, Lon2a, E. Merck-Darmstadt, Rhc ne-Poulenc, Sumitomo Pharmaceutical, E. Sung, and Tanabe Seiyaku (100). Worldwide production of biotin in 1994 was approximately 60 metric tons. The Hst price for pure biotin in 1995 was — 7.00/g whereas, the Hst price for technical feed-grade biotin was — 5.50/g. Biotin is used in various pharmaceutical, food, and special dietary products, including multivitamin preparations in Hquid, tablet, capsule, or powder forms. One of the commercially available products of i7-biotin is Britrit-1, which is a 1% biotin trituration used in food premixes. 

L-Fohc acid is available as a crystalline dihydrate containing 8% water. Approximately 80% of the commercial production is consumed for feed enrichment in animal nutrition. FoHc acid is being offered by the pharmaceutical industry for therapeutic and prophylactic use (see Pharmaceuticals). Pharmacological doses of fohc acid are commonly used as a rescue dose during cancer chemotherapy, in women using oral contraceptives, and alcohoHcs. Several studies have provided evidence that multivitamins or foHc acid (0.8—4 mg/day) supplementation prevent the majority of neural tube defects (101). 

Both nicotinic acid and nicotinamide have been used in the enrichment of bread, flour, and other grain-derived products. Animal feed is routinely supplemented with nicotinic acid and nicotinamide. Nicotinamide is also used in multivitamin preparations. Nicotinic acid is rarely used in this appHcation. The amide and carboxyHc acid have been used as a hrightener in electroplating baths and as stabili2er for pigmentation in cured meats. 

The primary uses of pyridoxine hydrochloride are in multivitamin supplement tablets and for fortification of human food and animal feed, especially for poultry and pigs. Most breakfast cereals and infant formulas in the United States are supplemented. Lesser amounts are used therapeutically to correct deficiencies or to treat specific disorders. Pyridoxine hydrochloride has been used experimentally to treat a variety of conditions with varying degrees of effectiveness (4,23). Pyridoxine hydrochloride is readily incorporated into premixes and foods. 

Polarography is appHed in the presence of other vitamins, eg, in multivitamin tablets, without separation. The polarography of flavins is reviewed in Reference 71. 

Flavin mononucleotide was first isolated from the yellow en2yme in yeast by Warburg and Christian in 1932 (4). The yellow en2yme was spHt into the protein and the yellow prosthetic group (coen2yme) by dialysis under acidic conditions. Flavin mononucleotide was isolated as its crystalline calcium salt and shown to be riboflavin-5Lphosphate its stmeture was confirmed by chemical synthesis by Kuhn and Rudy (94). It is commercially available as the monosodium salt dihydrate [6184-17 /, with a water solubiUty of more than 200 times that of riboflavin. It has wide appHcation in multivitamin and B-complex solutions, where it does not require the solubili2ers needed for riboflavin. 

Most of the thiamine sold worldwide is used for dietary supplements. Primary market areas include the following appHcations addition to feed formulations, eg, poultry, pigs, catde, and fish (see Feeds and feed additives) fortification of refined foods, eg, flours, rice, and cereal products and incorporation into multivitamins. Small amounts are used in medicine to treat deficiency diseases and other conditions, in agriculture as an additive to ferti1i2ers (qv), and in foods as flavorings. Generally for dry formulations, the less soluble, nonhygroscopic nitrate is preferred. Only the hydrochloride can be used for intravenous purposes. Coated thiamine is used where flavor is a factor. 

Preferably, high pressure Hquid chromatography (hplc) is used to separate the active pre- and cis-isomers of vitamin D from other isomers and allows their analysis by comparison with the chromatograph of a sample of pure reference i j -vitainin D, which is equiUbrated to a mixture of pre- and cis-isomers (82,84,85). This method is more sensitive and provides information on isomer distribution as well as the active pre- and cis-isomer content of a vitamin D sample. It is appHcable to most forms of vitamin D, including the more dilute formulations, ie, multivitamin preparations containing at least 1 lU/g (AOAC Methods 979.24 980.26 981.17 982.29 985.27) (82). The practical problem of isolation of the vitamin material from interfering and extraneous components is the limiting factor in the assay of low level formulations. 

It is known that Selenium catalyzes reaction of some dye reduction by Sulphide. On this basis spectrophotometric and test-techniques for Selenium determination are developed. Inefficient reproducibility and low sensitivity are their deficiencies. In the present work, solid-phase reagent on silica gel modified first with quaternary ammonium salt and then by Indigocarmine was proposed for Selenium(IV) test-determination. Optimal conditions for the Selenium determination by method of fixed concentration were found. The detection limit of Se(IV) is 10 ftg/L = 2 ng/sample). Calibration curve is linear in the range 50-400 ftg/L of Se(IV). The proposed method is successfully applied to the Selenium determination in multivitamins and bioadditions. 

If your patient with parkinsonism is taking levodopa, he must be careful to avoid vitamin B6 (pyridoxine) because it may interfere with the therapeutic effects of the drug. Most multivitamin supplements contain vitamin B6. Therefore, be sure to instruct your patient to check with his health care provider before taking any vitamin supplements. 

Avoid die use of multivitamin preparations unless such use has been approved by the primary healtii care provider. 

The identification of co-occurring medical problems is an important element in detoxification (Naranjo and Sellers 1986). Good supportive care and treatment of concurrent illness, including fluid and electrolyte repletion, are essential (Naranjo and Sellers 1986). Administration of thiamine (50—100 mg/day po or im) and multivitamins is a low-cost, low-risk intervention for the prophylaxis and treatment of alcohol-related neurological disturbances. 

One other study deserves a mention. The Cancer Prevention Study 11 was a prospective investigation using a very large cohort of over one million adult Americans, in which the effects of commercial multivitamin supplements and vitamins A, C or E on mortality were studied, during a follow-up period of seven years. The results were complex in that the use of multivitamins plus vitamins A, C and/or E significantly reduced the risk of lung cancer in both former smokers and life-long non-smokers, but vitamins A, C and E apparently increased the risk in current smokers. 

GIOVANNUCCI E, STAMPFER M J, COLDITZ G A, HUNTER J, FUCHS C, ROSNER B A, SPEIZER F E and WILLETT w c (1998) Multivitamin use, folate, and colon cancer in women in the Nurses Health Study , Ann Intern Med, 129, 517-24. 

All baboons had served in studies of intravenous self-injection with a variety of drugs. They had continuous access to water via a drinking tube and to food pellets (as described below) and received two pieces of fresh fruit and a multivitamin daily. 

Ibuprofen 600 mg twice daily for arthritis pain Vitamin B12 once daily Multivitamin daily Aspirin 325 mg once daily... 

Albuterol (salbutamol) metered-dose inhaler as needed Ortho-Tri-Cyclen Lo by mouth daily Echinacea 1 to 2 tablets by mouth daily as needed Multivitamin 1 tablet by mouth daily... 

Atorvastatin 40 mg PO once daily Hydrochlorothiazide 25 mg PO once daily Amlodipine 5 mg PO once daily Lantus insulin 30 units per day Multivitamin 1 tablet daily Pantoprazole 40 mg PO once daily Maalox 15 mL PO 4 times daily as needed for heartburn/stomach upset... 

Water-soluble vitamins removed by hemodialysis (HD) contribute to malnutrition and vitamin deficiency syndromes. Patients receiving HD often require replacement of water-soluble vitamins to prevent adverse effects. The vitamins that may require replacement are ascorbic acid, thiamine, biotin, folic acid, riboflavin, and pyridoxine. Patients receiving HD should receive a multivitamin B complex with vitamin C supplement, but should not take supplements that include fat-soluble vitamins, such as vitamins A, E, or K, which can accumulate in patients with renal failure. 

There is usually no need to supplement with specific vitamins. Patients should be encouraged to eat a well balanced diet and should also take a multivitamin and mineral supplement. Some clinicians recommend vitamins C and E for their antioxidant properties however, no significant improvements have been shown compared to placebo. Encourage patients to eat a diet rich in vitamin C and E (i.e., bright colored fruits and vegetables, nuts, and whole grains). Metabolism of levodopa may cause elevated homocysteine concentrations that... 

Advise most women of childbearing potential to take a multivitamin containing 400 meg folic acid. 

Counsel all women of childbearing potential regarding lifestyle modifications that may improve pregnancy outcome. These include healthy eating habits, multivitamin use, cessation of tobacco use, cessation of illicit substance use, and moderation of alcohol intake.15... 

Vitamin D is often combined in varying amounts with calcium salts. A multiple vitamin is another good source of vitamin D. Most multivitamins contain 400 IU per tablet. Vitamin D is also available as a single entity. Doses above 2000 IU/day should be avoided owing to the risk of hypercalciuria and hypercalcemia. Ergocalciferol (vitamin D2) and... 

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