RE Prenatal Multivitamin with Iron

Uses

Vitamin C is used for prevention and treatment of scurvy. It may be used for pregnancy, lactation, infection, trauma, burns, cold exposure, following surgery, fever, stress, peptic ulcer, cancer, methaemoglobinaemia and in infants receiving unfortified formulas. It is also prescribed for haematuria, dental caries, pyorrhea, acne, infertility, atherosclerosis, fractures, leg ulcers, hay fever, vascular thrombosis prevention, levodopa toxicity, succinyl-choline toxicity, arsenic toxicity etc. To reduce the risk of stroke in the elderly, long-term supplementation with Vitamin C is essential.

Vitamin D is used to treat and prevent bone disorders (such as rickets, osteomalacia). Vitamin D is made by the body when skin is exposed to sunlight. Sunscreen, protective clothing, limited exposure to sunlight, dark skin, and age may prevent getting enough vitamin D from the sun.

Vitamin D with calcium is used to treat or prevent bone loss (osteoporosis). Vitamin D is also used with other medications to treat low levels of calcium or phosphate caused by certain disorders (such as hypoparathyroidism, pseudohypoparathyroidism, familial hypophosphatemia). It may be used in kidney disease to keep calcium levels normal and allow normal bone growth.

This preparation is used for Pernicious anemia,Vitamin B12 deficiency due to low intake from food,Thyrotoxicosis, Hemorrhage, Malignancy, Liver or kidney disease,Gastric bypass surgery, Total or partial gastrectomy, Gluten enteropathy or sprue, Folic acid deficiency, Macrocytic anaemia

Prophylaxis of megaloblastic anaemia in pregnancy, Supplement for women of child-bearing potential, Folate-deficient megaloblastic anaemia, Prophylaxis of neural tube defect in pregnancy

Iron is an essential element commonly used for the treatment of patients with documented iron deficiency.

Used in preventing and treating iron-deficiency anemia.

Preventing and treating riboflavin deficiency and conditions related to riboflavin deficiency.

Cataracts, an eye disorder. People who eat more riboflavin as part of their diet seems to have a lower risk of developing cataracts. Also, taking supplements containing riboflavin plus niacin seems to help prevent cataracts.

High amounts of homocysteine in the blood (hyperhomocysteinemia). Some people are unable to convert the chemical homocysteine into the amino acid methionine. People with this condition, especially those with low riboflavin levels, have high amounts of homocysteine in the blood. Taking riboflavin for 12 weeks seems to reduce homocysteine levels by up to 40% in some people with this condition. Also, certain antiseizure drugs can increase homocysteine in the blood. Taking riboflavin along with folic acid and pyridoxine seems to lower homocysteine levels by 26% in people with high homocysteine levels due to antiseizure drugs.

Migraine headaches. Taking high-dose riboflavin (400 mg/day) seems to significantly reduce the number of migraine headache attacks. However, taking riboflavin does not appear to reduce the amount of pain or the amount of time a migraine headache lasts. Also, taking lower doses of riboflavin (200 mg/day) does not seem to reduce the number of migraine headache attacks.

Effective for:

• Vitamin A deficiency. Taking vitamin A by mouth is effective for preventing and treating symptoms of vitamin A deficiency. Vitamin A deficiency can occur in people with protein deficiency, diabetes, over-active thyroid, fever, liver disease, cystic fibrosis, or an inherited disorder called abetalipoproteinemia.

Possibly Effective for:

• Breast cancer. Premenopausal women with a family history of breast cancer who consume high levels of vitamin A in their diet seem to have reduced risk of developing breast cancer. It is not known if taking vitamin A supplements has the same benefit.
• Cataracts. Research suggests that high intake of vitamin A in the diet is linked to a lower risk of developing cataracts.
• Diarrhea related to HIV. Taking vitamin A along with conventional medicines seems to decrease the risk of death from diarrhea in HIV-positive children with vitamin A deficiency.
• Malaria. Taking vitamin A by mouth seems to decrease malaria symptoms in children less than 3 years-old living in areas where malaria is common.
• Measles. Taking vitamin A by mouth seems to reduce the risk of measles complications or death in children with measles and vitamin A deficiency.
• Precancerous lesions in the mouth (oral leukoplakia). Research suggests that taking vitamin A can help treat precancerous lesions in the mouth.
• Recovery from laser eye surgery (photoreactive keratectomy). Taking vitamin A by mouth along with vitamin E seems to improve healing after laser eye surgery.
• Complications after pregnancy. Taking vitamin A seems to reduce the risk of diarrhea and fever after pregnancy in malnourished women.
• Complications during pregnancy. Taking vitamin A by mouth seems to reduce the risk of death and night blindness during pregnancy in malnourished women.
• Eye disease affecting the retina (retinitis pigmentosa). Research suggests that taking vitamin A can slow the progression of an eye disease that causes damage to the retina.

RE Prenatal Multivitamin with Iron is also used to associated treatment for these conditions: Common Cold, Deficiency, Vitamin A, Deficiency, Vitamin D, Fever, Flu caused by Influenza, Folate deficiency, Iron Deficiency (ID), Iron Deficiency Anemia (IDA), Oral bacterial infection, Scurvy, Vitamin C Deficiency, Vitamin Deficiency, Nutritional supplementation, Vitamin supplementationCalcium and Vitamin D Deficiencies, Deficiency of Vitamin D3, Deficiency, Vitamin A, Deficiency, Vitamin D, Fracture Bone, Hip Fracture, Hypoparathyroidism, Hypophosphatemia, Familial, Menopause, Osteomalacia, Osteoporosis, Postmenopausal Osteoporosis, Vertebral Fractures, Vitamin D Resistant Rickets, Vitamin Deficiency, Severe Bone Resorption, Spine fracture, Calcium supplementation, Nutritional supplementation, Vitamin D Supplementation, Vitamin supplementationAnemia, Anemia, Pernicious, Combined Vitamin B1 and B12 deficiency, Convalescence, Diabetic Neuropathies, Folate deficiency, Iron Deficiency Anemia (IDA), Neuritis, Vitamin B1 deficiency, Vitamin B12 Deficiency, Vitamin B12 concentration, Vitamin B6 Deficiency, Vitamin Deficiency, Nutritional supplementation, Vitamin supplementationAnaemia folate deficiency, Folate deficiency, Iron Deficiency (ID), Iron Deficiency Anemia (IDA), Latent Iron Deficiency, Neural Tube Defects (NTDs), Vitamin Deficiency, Methotrexate toxicity, Nutritional supplementationAnemia, Iron Deficiency (ID), Iron Deficiency Anemia (IDA), Restless Legs Syndrome (RLS), Concomitant myelosuppressive chemotherapy, Nutritional supplementation, Dietary supplementationAriboflavinosis, Beriberi, Constipation, Functional Gastrointestinal Disorders, Joint Pain, Metabolic cardiomyopathy, Migraine, Neuralgia, Peripheral neuritis, Peripheral paralysis, Soreness, Muscle, Vitamin B complex deficiency, Vitamin B1 deficiency, Vitamin Deficiency, Wernicke's encephalopathy, Dietary and Nutritional Therapies, Nutritional supplementation, Vitamin supplementation, Dietary supplementationDeficiency, Vitamin A, Deficiency, Vitamin D, Degenerative Retinal Disorders, Disorder of the Epithelium, Disorder of the Mesoderm, Inner ear disorder, Vitamin Deficiency, Vitamin E Deficiency, Nutritional supplementation

How RE Prenatal Multivitamin with Iron works

In humans, an exogenous source of ascorbic acid is required for collagen formation and tissue repair by acting as a cofactor in the posttranslational formation of 4-hydroxyproline in -Xaa-Pro-Gly- sequences in collagens and other proteins. Ascorbic acid is reversibly oxidized to dehydroascorbic acid in the body. These two forms of the vitamin are believed to be important in oxidation-reduction reactions. The vitamin is involved in tyrosine metabolism, conversion of folic acid to folinic acid, carbohydrate metabolism, synthesis of lipids and proteins, iron metabolism, resistance to infections, and cellular respiration.

Most individuals naturally generate adequate amounts of vitamin D through ordinary dietary intake of vitamin D (in some foods like eggs, fish, and cheese) and natural photochemical conversion of the vitamin D3 precursor 7-dehydrocholesterol in the skin via exposure to sunlight .

Conversely, vitamin D deficiency can often occur from a combination of insufficient exposure to sunlight, inadequate dietary intake of vitamin D, genetic defects with endogenous vitamin D receptor, or even severe liver or kidney disease . Such deficiency is known for resulting in conditions like rickets or osteomalacia, all of which reflect inadequate mineralization of bone, enhanced compensatory skeletal demineralization, resultant decreased calcium ion blood concentrations, and increases in the production and secretion of parathyroid hormone . Increases in parathyroid hormone stimulate the mobilization of skeletal calcium and the renal excretion of phosphorus . This enhanced mobilization of skeletal calcium leads towards porotic bone conditions .

Ordinarily, while vitamin D3 is made naturally via photochemical processes in the skin, both itself and vitamin D2 can be found in various food and pharmaceutical sources as dietary supplements. The principal biological function of vitamin D is the maintenance of normal levels of serum calcium and phosphorus in the bloodstream by enhancing the efficacy of the small intestine to absorb these minerals from the diet . At the liver, vitamin D3 or D2 is hydroxylated to 25-hydroxyvitamin D and then finally to the primary active metabolite 1,25-dihydroxyvitamin D in the kidney via further hydroxylation . This final metabolite binds to endogenous vitamin d receptors, which results in a variety of regulatory roles - including maintaining calcium balance, the regulation of parathyroid hormone, the promotion of the renal reabsorption of calcium, increased intestinal absorption of calcium and phosphorus, and increased calcium and phosphorus mobilization of calcium and phosphorus from bone to plasma to maintain balanced levels of each in bone and the plasma .

In particular, calcitriol interacts with vitamin D receptors in the small intestine to enhance the efficiency of intestinal calcium and phosphorous absorption from about 10-15% to 30-40% and 60% increased to 80%, respectively . Furthermore, calcitriol binds with vitamin D receptors in osteoblasts to stimulate a receptor activator of nuclear factor kB ligand (or RANKL) which subsequently interacts with receptor activator of nuclear factor kB (NFkB) on immature preosteoclasts, causing them to become mature bone-resorbing osteoclasts . Such mature osteoclasts ultimately function in removing calcium and phosphorus from bone to maintain blood calcium and phosphorus levels . Moreover, calcitriol also stimulates calcium reabsorption from the glomerular filtrate in the kidneys .

Additionally, it is believed that when calcitriol binds with nuclear vitamin D receptors, that this bound complex itself binds to retinoic acid X receptor (RXR) to generate a heterodimeric complex that consequently binds to specific nucleotide sequences in the DNA called vitamin D response elements . When bound, various transcription factors attach to this complex, resulting in either up or down-regulation of the associated gene's activity. It is thought that there may be as much as 200 to 2000 genes that possess vitamin D response elements or that are influenced indirectly to control a multitude of genes across the genome . It is in this way that cholecalciferol is believed to function in regulating gene transcription associated with cancer risk, autoimmune disorders, and cardiovascular disease linked to vitamin D deficiency . In fact, there has been some research to suggest calcitriol may also be able to prevent malignancies by inducing cellular maturation and inducing apoptosis and inhibiting angiogenesis, exhibit anti-inflammatory effects by inhibiting foam cell formation and promoting angiogenesis in endothelial colony-forming cells in vitro, inhibit immune reactions by enhancing the transcription of endogenous antibiotics like cathelicidin and regulate the activity and differentiation of CD4+ T cells, amongst a variety of other proposed actions .

Vitamin B12 serves as a cofactor for methionine synthase and L-methylmalonyl-CoA mutase enzymes. Methionine synthase is essential for the synthesis of purines and pyrimidines that form DNA. L-methylmalonyl-CoA mutase converts L-methylmalonyl-CoA to succinyl-CoA in the degradation of propionate , an important reaction required for both fat and protein metabolism. It is a lack of vitamin B12 cofactor in the above reaction and the resulting accumulation of methylmalonyl CoA that is believed to be responsible for the neurological manifestations of B12 deficiency . Succinyl-CoA is also necessary for the synthesis of hemoglobin .

In tissues, vitamin B12 is required for the synthesis of methionine from homocysteine. Methionine is required for the formation of S-adenosylmethionine, a methyl donor for nearly 100 substrates, comprised of DNA, RNA, hormones, proteins, as well as lipids . Without vitamin B12, tetrahydrofolate cannot be regenerated from 5-methyltetrahydrofolate, and this can lead to functional folate deficiency , . This reaction is dependent on methylcobalamin (vitamin B12) as a co-factor and is also dependent on folate, in which the methyl group of methyltetrahydrofolate is transferred to homocysteine to form methionine and tetrahydrofolate. Vitamin B12 incorporates into circulating folic acid into growing red blood cells; retaining the folate in these cells . A deficiency of vitamin B12 and the interruption of this reaction leads to the development of megaloblastic anemia.

Folic acid, as it is biochemically inactive, is converted to tetrahydrofolic acid and methyltetrahydrofolate by dihydrofolate reductase (DHFR). These folic acid congeners are transported across cells by receptor-mediated endocytosis where they are needed to maintain normal erythropoiesis, synthesize purine and thymidylate nucleic acids, interconvert amino acids, methylate tRNA, and generate and use formate. Using vitamin B12 as a cofactor, folic acid can normalize high homocysteine levels by remethylation of homocysteine to methionine via methionine synthetase.

Iron is necessary for the production of hemoglobin. Iron-deficiency can lead to decreased production of hemoglobin and a microcytic, hypochromic anemia.

Binds to riboflavin hydrogenase, riboflavin kinase, and riboflavin synthase. Riboflavin is the precursor of flavin mononucleotide (FMN, riboflavin monophosphate) and flavin adenine dinucleotide (FAD). The antioxidant activity of riboflavin is principally derived from its role as a precursor of FAD and the role of this cofactor in the production of the antioxidant reduced glutathione. Reduced glutathione is the cofactor of the selenium-containing glutathione peroxidases among other things. The glutathione peroxidases are major antioxidant enzymes. Reduced glutathione is generated by the FAD-containing enzyme glutathione reductase.

Vision:Vitamin A (all-trans retinol) is converted in the retina to the 11-cis-isomer of retinaldehyde or 11-cis-retinal. 11-cis-retinal functions in the retina in the transduction of light into the neural signals necessary for vision. 11-cis-retinal, while attached to opsin in rhodopsin is isomerized to all-trans-retinal by light. This is the event that triggers the nerve impulse to the brain which allows for the perception of light. All-trans-retinal is then released from opsin and reduced to all-trans-retinol. All-trans-retinol is isomerized to 11-cis-retinol in the dark, and then oxidized to 11-cis-retinal. 11-cis-retinal recombines with opsin to re-form rhodopsin. Night blindness or defective vision at low illumination results from a failure to re-synthesize 11-cis retinal rapidly.
Epithelial differentiation: The role of Vitamin A in epithelial differentiation, as well as in other physiological processes, involves the binding of Vitamin A to two families of nuclear retinoid receptors (retinoic acid receptors, RARs; and retinoid-X receptors, RXRs). These receptors function as ligand-activated transcription factors that modulate gene transcription. When there is not enough Vitamin A to bind these receptors, natural cell differentiation and growth are interrupted.

Dosage

RE Prenatal Multivitamin with Iron dosage

vitamin C is usually administered orally. When oral administration is not feasible or when malabsorption is suspected, the drug may be administered IM, IV, or subcutaneously. When given parenterally, utilization of the vitamin reportedly is best after IM administration and that is the preferred parenteral route.

For intravenous injection, dilution into a large volume parenteral such as Normal Saline, Water for Injection, or Glucose is recommended to minimize the adverse reactions associated with intravenous injection.

The average protective dose of vitamin C for adults is 70 to 150 mg daily. In the presence of scurvy, doses of 300 mg to 1 g daily are recommended. However, as much as 6 g has been administered parenterally to normal adults without evidence of toxicity.

To enhance wound healing, doses of 300 to 500 mg daily for a week or ten days both preoperatively and postoperatively are generally considered adequate, although considerably larger amounts have been recommended. In the treatment of burns, doses are governed by the extent of tissue injury. For severe burns, daily doses of 1 to 2 g are recommended. In other conditions in which the need for vitamin C is increased, three to five times the daily optimum allowances appear to be adequate.

Parenteral drug products should be inspected visually for particulate matter and discoloration prior to administration, whenever the solution and container permit.

Oral solution: Colecalciferol (Vitamin D3) is recommended 5-10 mcg or 1-2ml (200-400 IU)/day or as directed by the physician.

Chewable tablet: Cholecalciferol (Vitamin D3) is recommended 100 IU (1 tablet) daily, or as directed by physician. Take the medicine with food or within 1 hour after a meal. Place the tablet in mouth swallow after chewing.

Injection:

• Treatment of Cholecalciferol deficiency: 40,000 lU/week for 7 weeks, followed by maintenance therapy (1400-2000 lU/day). Follow-up 25 (OH) D measurements should be made approximately 3 to 4 months after initiating maintenance therapy to confirm that the target level has been achieved.
• Prevention of Vitamin D deficiency: 20,000 lU/Month.
• Treatment of Vitamin D deficiency:12-18 years: 20,000 IU, once every 2 weeks for 6 weeks. Prevention of Vitamin D deficiency, 12-18 years: 20,000 IU, once every 6 weeks.

Usual Adult Dose for Pernicious Anemia

Initial dose: 1000 mcg intramuscularly or deep subcutaneous once a day for 6 to 7 daysIf clinical improvement and reticulocyte response is seen from the above dosing:

• 100 mcg every other day for 7 doses, then
• 100 mcg every 3 to 4 days for 2 to 3 weeks, then
• Maintenance dose: 100 to 1000 mcg monthly

Administer concomitant folic acid if needed. Chronic treatment should be done with an oral preparation in patients with normal intestinal absorption.

Usual Adult Dose for B12 Nutritional Deficiency: 25 to 2000 mcg orally daily

Usual Adult Dose for Schilling Test: 1000 mcg intramuscularly is the flushing dose

Usual Pediatric Dose for B12 Nutritional Deficiency: 0.5 to 3 mcg daily

Supplement for women of child-bearing potential: 0.4 mg daily.

Folate-deficient megaloblastic anaemia: 5 mg daily for 4 mth, up to 15 mg daily in malabsorption states. Continued dosing at 5 mg every 1-7 days may be needed in chronic haemolytic states, depending on the diet and rate of haemolysis.

Prophylaxis of neural tube defect in pregnancy: 4 or 5 mg daily starting before pregnancy and continued through the 1st trimester.

Prophylaxis of megaloblastic anaemia in pregnancy: 0.2-0.5 mg daily.

For treating low levels of riboflavin (riboflavin deficiency) in adults: 5-30 mg of riboflavin (Vitamin B2) daily in divided doses.

For preventing migraine headaches: 400 mg of riboflavin (Vitamin B2) per day. It may take up to three months to get best results.

For preventing cataracts: a daily dietary intake of approximately 2.6 mg of riboflavin (Vitamin B2) has been used. A combination of 3 mg of riboflavin (Vitamin B2) plus 40 mg of niacin daily has also been used.

The daily recommended dietary allowances (RDAs) of riboflavin (Vitamin B2) are:

• Infants 0-6 months: 0.3 mg
• Infants 7-12 months: 0.4 mg
• Children 1-3 years: 0.5 mg
• Children 4-8 years: 0.6 mg
• Children 9-13 years: 0.9 mg
• Men 14 years or older: 1.3 mg
• Women 14-18 years: 1 mg
• Women over 18 years: 1.1 mg
• Pregnant women: 1.4 mg
• Breastfeeding women: 1.6 mg

Vitamin A deficiency For severe deficiency with corneal changes: 500,000 unit/day for 3 days, followed by 50,000 unit/day for 2 wk and then 10,000-20,000 unit/day for 2 mth as follow-up therapy.

For cases without corneal changes: 10,000-25,000 unit/day until clinical improvement occurs (usually 1 -2 wk).

May be taken with or without food.

Side Effects

Ascorbic acid does not seem to have any important adverse effects at dosages less than 4 mg/day. Larger dose may cause diarrhoea or formation of renal calculi of calcium oxalate in patients with renal impairment. Ingestion of more than 600 mg daily have a diuretic action.

Generally all nutritional supplements are considered to be safe and well tolerable. However, few side-effects can generally occur including hypercalcaemia syndrome or Calcium intoxication (depending on the severity and duration of hypercalcaemia), occasional acute symptoms include anorexia, headache, nausea, vomiting, abdominal pain or stomach ache and constipation with the administration of Colecaciferol.

Arthralgia (12%), Dizziness (12%), Headache (12%), Nasopharyngitis (12%), Anaphylaxis, Angioedema, Congestive heart failure, Peripheral vascular disease,Pulmonary edema, Diarrhea, Dyspepsia, Polycythemia vera, Sore throat, Nervousness, Rhinitis, Glossitis, Hypoesthesia

GI disturbances, hypersensitivity reactions; bronchospasm.

Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat. Riboflavin may cause your urine to turn a yellow-orange color, but this is usually not a harmful side effect.

Hypervitaminosis A characterised by fatigue, irritability, anorexia, weight loss, vomiting and other Gl disturbances, low-grade fever, hepatosplenomegaly, skin changes, alopoecia, dry hair, cracking and bleeding lips, SC swelling, nocturia, pains in bones and joints.

Toxicity

Chronic or acute administration of excessive doses of cholecalciferol may lead to hypervitaminosis D, manifested by hypercalcemia and its sequelae . Early symptoms of hypercalcemia may include weakness, fatigue, somnolence, headache, anorexia, dry mouth, metallic taste, nausea, vomiting, vertigo, tinnitus, ataxia, and hypotonia . Later and possibly more serious manifestation include nephrocalcinosis, renal dysfunction, osteoporosis in adults, impaired growth in children, anemia, metastatic calcification, pancreatitis, generalized vascular calcification, and seizures .

Safety of doses in excess of 400 IU (10mcg) of vitamin D3 daily during pregnancy has not been established . Maternal hypercalcemia, possibly caused by excessive vitamin D intake during pregnancy, has been associated with hypercalcemia in neonates, which may lead to supravalvular aortic stenosis syndrome, the features of which may include retinopathy, mental or growth retardation, strabismus, and other effects . Hypercalcemia during pregnancy may also lead to suppression of parathyroid hormone release in the neonate, resulting in hypocalcemia, tetany, and seizures .

Vitamin D is deficient in maternal milk; therefore, breastfed infants may require supplementation. Use of excessive amounts of Vitamin D in nursing mothers may result in hypercalcemia in infants. Doses of Vitamin D3 in excess of 10 µg daily should not be administered daily to nursing women.

LD50 Oral (mouse): > 5,000 mg/kg .

General toxicity

Vitamin B12 is generally non-toxic, even at higher doses. Mild, transient diarrhea, polycythemia vera, peripheral vascular thrombosis, itching, transitory exanthema, a feeling of swelling of entire body, pulmonary edema and congestive heart failure in early treatment stages, anaphylactic shock and death have been observed after vitamin B12 administration .

Carcinogenesis and mutagenesis

Long term studies in animals examining the carcinogenic potential of any of the vitamin B12 formulations have not completed to date. There is no evidence from long-term use in patients with pernicious anemia that vitamin B12 has carcinogenic potential. Pernicious anemia is known to be associated with an increased incidence of stomach carcinoma, however, this malignancy has been attributed to the underlying cause of pernicious anemia and has not been found to be related to treatment with vitamin B12 .

Use in pregnancy

No adverse effects have been reported with ingestion of normal daily requirements during pregnancy .

A note on the use of the nasal spray in pregnancy

Although vitamin B12 is an essential vitamin and requirements are increased during pregnancy, it is currently unknown whether the nasal spray form can cause fetal harm when administered to a pregnant woman or can affect reproduction capacity. The nasal spray form should be given to a pregnant woman only if clearly needed, as it is considered a pregnancy category C drug in this form. Sufficient well-controlled studies have not been done to this date in pregnant women .

Use in lactation

Vitamin B12 has been found distributed into the milk of nursing women in concentrations similar to the maternal blood vitamin B12 concentrations. No adverse effects have been reported to date with intake of normal required doses during lactation .

IPR-MUS LD₅₀ 85 mg/kg,IVN-GPG LD₅₀ 120 mg/kg, IVN-MUS LD₅₀ 239 mg/kg, IVN-RAT LD₅₀ 500 mg/kg, IVN-RBT LD₅₀ 410 mg/kg

Acute iron overdosage can be divided into four stages. In the first stage, which occurs up to six hours after ingestion, the principal symptoms are vomiting and diarrhea. Other symptoms include hypotension, tachycardia and CNS depression ranging from lethargy to coma. The second phase may occur at 6-24 hours after ingestion and is characterized by a temporary remission. In the third phase, gastrointestinal symptoms recur accompanied by shock, metabolic acidosis, coma, hepatic necrosis and jaundice, hypoglycemia, renal failure and pulmonary edema. The fourth phase may occur several weeks after ingestion and is characterized by gastrointestinal obstruction and liver damage. In a young child, 75 milligrams per kilogram is considered extremely dangerous. A dose of 30 milligrams per kilogram can lead to symptoms of toxicity. Estimates of a lethal dosage range from 180 milligrams per kilogram and upwards. A peak serum iron concentration of five micrograms or more per ml is associated with moderate to severe poisoning in many.

Acute toxicity to vitamin A can occur when adults or children ingest >100x or >20x the RDA, respectively, over a period of hours or a few days. The RDA for vitamin A differs depending on age and sex and can range from 300 - 900 μg retinol activity equivalents (RAE) per day. Symptoms of acute systemic toxicity generally include mucocutaneous involvement (e.g. xerosis, cheilitis, skin peeling) and may involve mental status changes. Children are typically more susceptible to acute vitamin A toxicity - daily intakes of as little as 1500 IU/kg have been observed to result in toxicity.

Chronic vitamin A toxicity can develop following the long-term ingestion of high vitamin A doses. While there is a wide variation in the lowest toxic vitamin A dose, the ingestion of >25 000 IU daily for 6 years or 100,000 IU daily for 6 months is considered to be toxic. Chronic vitamin A toxicity can affect many organ systems and can lead to the development of osteoporosis and CNS effects (e.g. headaches).

Precaution

Ingestion of megadose (more than 1000 mg daily) of vitamin C during pregnancy has resulted in scurvy in neonates. Vitamin C in mega-doses has been contraindicated for patients with hyperoxaluria. Vitamin C itself is a reactive substance in the redox system and can give rise to false positive reactions in certain analytical tests for glucose, uric acid, creatine and occult blood.

People with the following conditions should exercise caution when considering taking vitamin D supplements: High blood Calcium or Phosphorus level, Heart problems, Kidney disease.

Vitamin D must be taken with adequate amounts of both Calcium and Magnesium supplementation. When Calcium level is low (due to insufficient vitamin D and calcium intake), the body activates the parathyroid gland, which produces PTH (parathyroid hormone). This hormone kick starts vitamin D hormone production and assists removal of Calcium from the bones to be used in more important functions such as neutralizing body acidity.

Intensive treatment of B12-deficient megaloblastic anemia may cause hypokalemia and sudden death. Use with caution in patients with Leber optic nerve atrophy. Thrombocytosis may occur with treatment of severe vitamin B12 megaloblastic anemia

Treatment resistance may occur in patients with depressed haematopoiesis, alcoholism, deficiencies of other vitamins. Neonates.

Cholestatic jaundice; fat-malabsorption conditions. Monitor patients closely for toxicity. Liver impairment and children.

Interaction

Potentially hazardous interactions: Ascorbic acid is incompatible in solution with aminophylline, bleomycin, erythromycin, lactobionate, nafcillin, nitrofurantoin sodium, conjugated oestrogen, sodium bicarbonate, sulphafurazole diethanolamine, chloramphenicol sodium succinate, chlorthiazide sodium and hydrocortisone sodium succinate.

Useful interactions: Ascorbic acid increases the apparent half-life of paracetamol and enhances iron absorption from the gastrointestinal tract.

Cholecalciferol is known to interact with Carbamazepine, Dactinomycin, Diuretics, Fosphenytoin, Miconazole, Phenobarbital, Phenytoin, Primidone

Absorption reduced by antibiotics, aminosalicylic acid, anticonvulsants, biguanides, cholestyramine, cimetidine, colchicine, K salts, methyldopa.

Antiepileptics, oral contraceptives, anti-TB drugs, alcohol, aminopterin, methotrexate, pyrimethamine, trimethoprim and sulphonamides may result to decrease in serum folate contrations. Decreases serum phenytoin concentrations.

Rate and extent of absorption may be affected by propantheline bromide.

Decreased absorption with neomycin. Increased risk of hypervitaminosis A with synthetic retinoids eg, acitretin, isotretinoin and tretinoin. Increased risk of toxicity when used with alcohol.

Volume of Distribution

Studies have determined that the mean central volume of distribution of administered cholecalciferol supplementation in a group of 49 kidney transplant patients was approximately 237 L .

Cobalamin is distributed to tissues and stored mainly in the liver and bone marrow .

Tetrahydrofolic acid derivatives are distributed to all body tissues but are stored primarily in the liver.

Elimination Route

70% to 90%

Cholecalciferol is readily absorbed from the small intestine if fat absorption is normal . Moreover, bile is necessary for absorption as well .

In particular, recent studies have determined aspects about the absorption of vitamin D, like the fact that a) the 25-hydroxyvitamin D metabolite of cholecalciferol is absorbed to a greater extent than the nonhydroxy form of cholecalciferol, b) the quantity of fat with which cholecalciferol is ingested does not appear to largely affect its bioavailability, and c) age does not apparently effect vitamin D cholecalciferol .

Vitamin B12 is quickly absorbed from intramuscular (IM) and subcutaneous (SC) sites of injection; with peak plasma concentrations achieved about 1 hour after IM injection .

Orally administered vitamin B12 binds to intrinsic factor (IF) during its transport through the stomach. The separation of Vitamin B12 and IF occurs in the terminal ileum when calcium is present, and vitamin B12 is then absorbed into the gastrointestinal mucosal cells. It is then transported by transcobalamin binding proteins . Passive diffusion through the intestinal wall can occur, however, high doses of vitamin B12 are required in this case (i.e. >1 mg). After the administration of oral doses less than 3 mcg, peak plasma concentrations are not reached for 8 to 12 hours, because the vitamin is temporarily retained in the wall of the lower ileum .

Folic acid is absorbed rapidly from the small intestine, primarily from the proximal portion. Naturally occurring conjugated folates are reduced enzymatically to folic acid in the gastrointestinal tract prior to absorption. Folic acid appears in the plasma approximately 15 to 30 minutes after an oral dose; peak levels are generally reached within 1 hour.

The efficiency of absorption depends on the salt form, the amount administered, the dosing regimen and the size of iron stores. Subjects with normal iron stores absorb 10% to 35% of an iron dose. Those who are iron deficient may absorb up to 95% of an iron dose.

Vitamin B2 is readily absorbed from the upper gastrointestinal tract.

Readily absorbed from the normal gastrointestinal tract

Half Life

16 days (3.4 hours in people who have excess levels of vitamin C)

At this time, there have been resources that document the half-life of cholecalciferol as being about 50 days while other sources have noted that the half-life of calcitriol (1,25-dihydroxyvitamin D3) is approximately 15 hours while that of calcidiol (25-hydroxyvitamin D3) is about 15 days .

Moreover, it appears that the half-lives of any particular administration of vitamin d can vary due to variations in vitamin d binding protein concentrations and genotype in particular individuals .

Approximately 6 days (400 days in the liver) .

66-84 minutes

1.9 hours

Clearance

Studies have determined that the mean clearance value of administered cholecalciferol supplementation in a group of 49 kidney transplant patients was approximately 2.5 L/day .

During vitamin loading, the kidney accumulates large amounts of unbound vitamin B12. This drug is cleared partially by the kidney, however, multiligand receptor megalin promotes the reuptake and reabsorption of vitamin B12 into the body , .

Elimination Route

It has been observed that administered cholecalciferol and its metabolites are excreted primarily in the bile and feces .

This drug is partially excreted in the urine . According to a clinical study, approximately 3-8 mcg of vitamin B12 is secreted into the gastrointestinal tract daily via the bile. In patients with adequate levels of intrinsic factor, all except approximately 1 mcg is reabsorbed. When vitamin B12 is administered in higher doses that saturate the binding capacity of plasma proteins and the liver, the unbound vitamin B12 is eliminated rapidly in the urine. The body storage of vitamin B12 is dose-dependent .

After a single oral dose of 100 mcg of folic acid in a limited number of normal adults, only a trace amount of the drug appeared in the urine. An oral dose of 5 mg in 1 study and a dose of 40 mcg/kg of body weight in another study resulted in approximately 50% of the dose appearing in the urine. After a single oral dose of 15 mg, up to 90% of the dose was recovered in the urine. A majority of the metabolic products appeared in the urine after 6 hours; excretion was generally complete within 24 hours. Small amounts of orally administered folic acid have also been recovered in the feces. Folic acid is also excreted in the milk of lactating mothers.

Pregnancy & Breastfeeding use

The drug is safe in normal doses in pregnant women, but a daily intake of 5 gm or more is reported to have caused abortion. The drug may be taken safely during lactation.

There is no evidence to suggest that vitamin D is teratogenic in humans even at very high doses. Colecalciferol should be used during pregnancy only if the benefits outweigh the potential risk to the fetus.

It should be assumed that exogenous Colecalciferol passes into the breast milk. In view of the potential for hypercalcaemia in the mother and for adverse reactions from Colecalciferol in nursing infants, mothers may breastfeed while taking Colecalciferol, provided that the serum Calcium levels of the mother and infant are monitored.

Pregnancy Category A. Adequate and well-controlled human studies have failed to demonstrate a risk to the fetus in the first trimester of pregnancy (and there is no evidence of risk in later trimesters).

Lactation: Drug distributed in milk.

Pregnancy Category A. Adequate and well-controlled human studies have failed to demonstrate a risk to the fetus in the first trimester of pregnancy (and there is no evidence of risk in later trimesters).

Riboflavin is LIKELY SAFE for pregnant or breast-feeding women when taken in the amounts recommended. The recommended amounts are 1.4 mg per day for pregnant women and 1.6 mg per day in breast-feeding women. Riboflavin is POSSIBLY SAFE when taken by mouth in larger doses, short-term. Some research shows that riboflavin is safe when taken at a dose of 15 mg once every 2 weeks for 10 weeks.

Pregnancy Category A. Adequate and well-controlled human studies have failed to demonstrate a risk to the fetus in the first trimester of pregnancy (and there is no evidence of risk in later trimesters).

Contraindication

Colecalciferol is contraindicated in all diseases associated with hypercalcaemia. It is also contraindicated in patients with known hypersensitivity to Colecalciferol (or medicines of the same class) and any of the constituent excipients. Colecalciferol is contraindicated if there is evidence of vitamin D toxicity.

Leber's disease, tobacco amblyopia.

Undiagnosed megaloblastic anaemia; pernicious, aplastic or normocytic anaemias.

Hypervitaminosis A; pregnancy (dose exceeding RDA).

Acute Overdose

Symptoms: anorexia, headache, vomiting, constipation, dystrophy (weakness, loss of weight), sensory disturbances, possibly fever with thirst, polyuria, dehydration, apathy, arrested growth and urinary tract infections. Hypercalcaemia ensues, with metastatic calcification of the renal cortex, myocardium, lungs and pancreas.

Treatment: Immediate gastric lavage or induction of vomiting to prevent further absorption. Liquid paraffin should be administered to promote faecal excretion. Repeated serum calcium determinations are advisable. If elevated calcium levels persist in the serum, phosphates and corticosteroids may be administered and measures instituted to bring about adequate diuresis.

Storage Condition

Should be stored in a dry place below 30˚C.

Store at 15-30° C.

Store at 15-30° C.

Innovators Monograph

You find simplified version here RE Prenatal Multivitamin with Iron