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Vitamin DAka: Vitamin D Replacement, Cholecalciferol, Ergocalciferol, Dihydrotachysterol

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  1. See also
    1. Bone
  2. Physiology
    1. Step 1: Start with 7-Dehydrocholesterol
      1. Skin exposure to sunlight or other ultraviolet light
    2. Step 2: Cholecalciferol (Vitamin D3)
      1. Metabolized in liver by Vitamin D3-25 hydroxylase
    3. Step 3: Calcidiol
      1. Metabolized in kidney by 25-OH-D3-1a hydroxylase
    4. Step 4: Calcitriol (active form of Vitamin D)
  3. Pathophysiology
    1. See Serum Calcium for calcium metabolism
    2. Sources
      1. Vitamin D synthesized in skin after exposed to sun
      2. Absorbed from small intestine
    3. Vitamin D circulates in blood as Calcidiol
    4. Vitamin D Deficiency seen in:
      1. Homebound elderly
      2. Inhabitants of Northern States
    5. Vitamin D Deficiency related conditions
      1. Children: Rickets
      2. Adults: Osteoporosis
  4. Indications
    1. Osteoporosis Prevention
    2. Vitamin D Deficiency
  5. Preparations: Dietary and Supplement Sources
    1. Fatty Fish
      1. Salmon
      2. Sardines
      3. Fish oils
    2. Eggs
    3. Butter
    4. Liver and other organ meats
    5. Vitamin D Fortified Milk (USA) contains 100 IU per cup
    6. Multi-Vitamin Contains 400 IU Vitamin D per tablet
  6. Signs: Vitamin D Deficiency
    1. See Vitamin D Deficiency
    2. Osteomalacia
    3. Muscular hypotonia
  7. Dosing: Adults (higher than current RDA)
    1. Age <50 years: 400-800 IU per day
    2. Age >50 years or Osteoporosis: 800-1000 IU per day (up to 2000 IU per day is safe)
  8. Dosing: Children with Vitamin D Deficiency (Rickets)
    1. Ergocalciferol (D2, Calciferol)
      1. Dose: 25-125 mcg (1-5000 IU) PO/IM for 6-12 weeks
    2. Cholecalciferol (D3, 40,000 IU/mg)
      1. Option 1: 125-250 mcg (5-10,000 IU) PO for 3 months
      2. Option 2: 15,000 mcg (600,000 IU) divided qid x1 day
    3. Dihydrotachysterol (DHT, 120,000 IU/mg)
      1. Option 1: 500 mcg (0.5 mg) for single dose or
      2. Option 2: 13-50 mcg PO per day until resolved
    4. References
      1. Khatib (2005) Consultant Pediatrician 4:33
  9. Dosing: Adults with Vitamin D Deficiency
    1. Mild (Serum 25-hydroxyvitamin D 8-15 ng/ml)
      1. Vitamin D options
        1. First line: Vitamin D 50,000 IU PO weekly for 6-8 weeks (typically 8 weeks)
        2. Parenteral: Vitamin D 20-25 IU/kg IV daily
        3. Maintenance after acute replacement: Vitamin D 800-1000 IU PO daily
      2. Calcium 1200 to 1500 mg orally daily
    2. Severe (Serum 25-hydroxyvitamin D <8 ng/ml)
      1. Vitamin D 50,000 IU orally daily for 1-3 weeks
      2. Then maintain as mild deficiency doses above
    3. Monitoring Vitamin D level at 2 months after starting therapy
      1. Goal 25-Hydroxyvitamin D >30-40 ng/ml
  10. Efficacy: Vitamin D in Osteoporosis Prevention
    1. Dutch Study of 348 women over age 70 years
      1. Given Vitamin D 400 IU or Placebo
      2. Vitamin D Group had greater BMD at 2 years
        1. Greater femoral neck Bone Mineral Density
        2. Placebo group had decreased Bone Mineral Density
      3. No change in femoral trachanter or distal radius BMD
    2. References
      1. Ooms (1995) J Clin Endocrinol Metab 80:1052
  11. References
    1. Holick (2007) N Engl J Med 357(3):266

Cholecalciferol (C0008318)

Definition (MSH)Derivative of 7-dehydroxycholesterol formed by ULTRAVIOLET RAYS breaking of the C9-C10 bond. It differs from ERGOCALCIFEROL in having a single bond between C22 and C23 and lacking a methyl group at C24.
Definition (CSP)produced in human and other animal tissue by photoactivation (normally sunlight on skin) of 7-dehydrocholesterol.
Definition (NCI)A steroid hormone produced in the skin when exposed to ultraviolet light or obtained from dietary sources. The active form of cholecalciferol, 1,25-dihydroxycholecalciferol (calcitriol) plays an important role in maintaining blood calcium and phosphorus levels and mineralization of bone. The activated form of cholecalciferol binds to vitamin D receptors and modulates gene expression. This leads to an increase in serum calcium concentrations by increasing intestinal absorption of phosphorus and calcium, promoting distal renal tubular reabsorption of calcium and increasing osteoclastic resorption.
Definition (PDQ)A steroid hormone produced in the skin when exposed to ultraviolet light or obtained from dietary sources. The active form of cholecalciferol, 1,25-dihydroxycholecalciferol (calcitriol) plays an important role in maintaining blood calcium and phosphorus levels and mineralization of bone. The activated form of cholecalciferol binds to vitamin D receptors and modulates gene expression. This leads to an increase in serum calcium concentrations by increasing intestinal absorption of phosphorus and calcium, promoting distal renal tubular reabsorption of calcium and increasing osteoclastic resorption. Check for "http://www.cancer.gov/Search/ClinicalTrialsLink.aspx?id=39734&idtype=1" active clinical trials or "http://www.cancer.gov/Search/ClinicalTrialsLink.aspx?id=39734&idtype=1&closed=1" closed clinical trials using this agent. ("http://nciterms.nci.nih.gov:80/NCIBrowser/ConceptReport.jsp?dictionary=NCI_Thesaurus&code=C48194" NCI Thesaurus)
ConceptsSteroid (T110) , Pharmacologic Substance (T121) , Vitamin (T127)
MSHD002762
EnglishActivated 7-dehydrocholesterol, Activated 7-dehydrocholesterol preparation, Calciol, Cholecalciferol, Cholecalciferol preparation, Colecalciferol, Colecalciferol preparation, D3 - Cholecalciferol, Delsterol, Vitamin D 3, VITAMIN D A 03, Vitamin D<sub>3</sub>, Vitamin D>3<, Vitamin D3, VITD - Cholecalciferol, Vtitamin D<sub>3</sub>, Vtitamin D>3<, Vtitamin D3
Spanish7-dehidrocolesterol activado, colecalciferol, D3 - colecalciferol, preparado con 7-dehidrocolesterol activado, preparado con colecalciferol, preparado de 7-dehidrocolesterol activado, vitamina D<sub>3</sub>, vitamina D>3<, vitamina D3
Parent ConceptsVitamin D (C0042866), Cholestenes (C0008375), Sterols (C0038323), Secosteroids (C0036532), [VT509] VITAMIN D, OTHER (C0973665), TO BE DELETED INGREDIENT PREPARATIONS (C1377153), Calcium regulating hormone (C0360589), Duplicate concept (C1274013)
SourcesAOD, CSP, LNC, MSH, MTH, MTHSPL, NCI, NDFRT, PDQ, RXNORM, SCTSPA, SNOMEDCT, VANDF
Derived from the NIH UMLS (Unified Medical Language System)


Dihydrotachysterol (C0012319)

Definition (MSH)A VITAMIN D that can be regarded as a reduction product of vitamin D2.
ConceptsSteroid (T110) , Pharmacologic Substance (T121) , Vitamin (T127)
MSHD004097
EnglishDHT preparation, Dichysterol preparation, Dihydrotachysterin, Dihydrotachysterol, Dihydrotachysterol preparation, Dihydrotachysterol<sub>2</sub> preparation, Dihydrotachysterol>2< preparation, Dihydrotachysterol2 preparation, Tachystin
Spanishdihidrotaquisterol, preparado con dihidrotaquisterol, preparado con dihidrotaquisterol<sub>2</sub>, preparado con dihidrotaquisterol>2<, preparado con dihidrotaquisterol2, preparado de DHT, preparado de dicisterol
Parent ConceptsVitamin D (C0042866), Cholestenes (C0008375), Ergocalciferols (C0014696), Sterols (C0038323), Dihydrotachysterol (C0012319), Secosteroids (C0036532)
SourcesAOD, CSP, MSH, NDFRT, RXNORM, SCTSPA, SNOMEDCT, VANDF
Derived from the NIH UMLS (Unified Medical Language System)


Ergocalciferol (C0014695)

Definition (NCI)Vitamin D2, a fat-soluble vitamin important for many biochemical processes including the absorption and metabolism of calcium and phosphorus. In vivo, ergocalciferol is formed after sun (ultraviolet) irradiation of plant-derived ergosterol, another form of vitamin D. Ergocalciferol is the form of vitamin D usually found in vitamin supplements. (NCI04)
ConceptsSteroid (T110) , Pharmacologic Substance (T121) , Vitamin (T127)
MSHD004872
EnglishActivated ergosterol preparation, Calciferol, Calciferol preparation, Ergocalciferol, Ergocalciferol preparation, Ergocalciferol product, Viosterol preparation, Vitamin D, Vitamin D 2, VITAMIN D A 02, Vitamin D<sub>2</sub>, Vitamin D<sub>2</sub> preparation, Vitamin D>2<, Vitamin D>2< preparation, Vitamin D2, Vitamin D2 preparation
Spanishergocalciferol, preparado con calciferol, preparado con ergocalciferol, preparado de calciferol, preparado de ergocalciferol, preparado de ergosterol activado, preparado de viosterol, preparado de vitamina D<sub>2</sub>, preparado de vitamina D>2<, preparado de vitamina D2, vitamina D<sub>2</sub>, vitamina D>2<, vitamina D2
Parent ConceptsVitamin D (C0042866), Ergocalciferol (C0014695), Ergocalciferols (C0014696)
SourcesAOD, CSP, LNC, MSH, MTH, MTHSPL, NCI, NDFRT, RXNORM, SCTSPA, SNOMEDCT, VANDF
Derived from the NIH UMLS (Unified Medical Language System)



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