9.6 Vitamins

General Notes
  • The use of vitamins as general "pick–me–ups" is of unproven value and, in the case of preparations containing vitamin A or D, may be harmful if the prescribed dose is exceeded.
  • Mega–vitamin therapy with water–soluble vitamins, such as ascorbic acid and pyridoxine, is unscientific and can be harmful.
  • Renavit® is a specific multivitamin preparation for use in dietary management of water soluble vitamin deficiency in renal failure patients receiving dialysis.  It is classed as a food for special medical purposes as approved by ACBS (Advisory Committee on Borderline Substances). 

9.6.1 Fat soluble vitamins in cystic fibrosis

First Choice:
vitamin A and D capsules
vitamin E capsules
Second Choice:
ADEKplus chewable tablets
Formulations/Dose
  • Vitamin A and D capsules (vitamin A 5000units, vitamin D 400units): 2-3 capsules daily
  • Vita-E® 75iu capsules equivalent to 50mg of D-alpha tocopherol: 3 capsules daily with pancreatic enzymes
  • ADEKplus chewable tablets[unlicensed preparation] (one tablet contains vitamin A 2700 units, vitamin D3 1000 units, vitamin E 100mg, vitamin K 5mg.  Also contains other vitamins and trace elements): 1-2 tablets daily
Prescribing Notes
  • If Vitamin K is required, ADEKplus reduces the pill burden and may be more cost effective than separate combinations.
  • Vitamin A and D can be toxic in overdose. Levels are monitored once per year, compliance checked and dose adjusted at the cystic fibrosis clinic.
  • The usual maximum recommended dose of vitamin A is 10,000units daily. This dose should not be exceeded in pregnancy.
9.6.2 Vitamin B group
Prescribing Notes
  • Vitamin B deficiency, other than B12, is rare. See section 9.1.2(a)
  • Pyridoxine (vitamin B6) deficiency may occur during isoniazid treatment. There is evidence to suggest that pyridoxine in doses not exceeding 100mg daily may provide some benefit in premenstrual syndrome.
  • For vitamin B supplementation in alcohol dependence, see section 4.10(g).
  • Vitamin B complex preparations are not recommended for prescribing.
9.6.3 Vitamin C

First Choice:
ascorbic acid
Dose
  • ascorbic acid tablets 50mg, 100mg, 200mg, 500mg: prevention of scurvy, 25–75mg daily; treatment of scurvy, not less than 250mg daily in divided doses.
Prescribing Notes
  • Divided doses are necessary due to the low renal threshold of ascorbic acid.
9.6.4 Vitamin D

Patients with severe renal impairment
First Choice:
alfacalcidol (1α–hydroxycholecalciferol)
Biochemical insufficiency
First Choice:
colecalciferol
Osteomalacia
First Choice:
colecalciferol  
Dose
  • colecalciferol capsules, tablets, 800 units (equivalent to 20 micrograms): see guideline for dosing: see BNF for different brands available and for the maximum daily dosing (as this differs between brands).
  • colecalciferol capsules, 3200 units (equivalent to 80 micrograms): see guideline for dosing.
  • colecalciferol oral solution 25000 units/mL: see BNF and guideline for dosing.
  • alfacalcidol capsules 250nanograms, 500nanograms, 1microgram; oral drops 2micrograms/mL; injection 2micrograms/mL: by mouth or intravenous injection, initially 1microgram daily (elderly, 500nanograms), adjusted to avoid hypercalcaemia; maintenance, usually 0.25–1microgram daily.
Prescribing Notes
  • Treatment of vitamin D deficiency should follow the NHS Lothian Adult Vitamin D guideline via the Edinburgh Centre for Endocrinology Handbook.  This guideline recommends treatment in a three level step-wise approach.
  • Colecalciferol is indicated in adults and elderly for prevention and treatment of vitamin D deficiency who require level 2 treatment. This means there is a biochemical insufficiency but the benefit of treatment is unclear.
  • Patients requiring level 3 treatment should receive colecalciferol oral solution (InVitaD3®).   Level 3 treatment is where there is osteomalacia, there are clear treatment benefits.
  • InVitaD3® is presented as single dose oral ampoules, the contents of the ampoule should be emptied directly into the mouth and swallowed, or emptied on to a spoon and taken orally.

  • Patients with severe renal impairment requiring vitamin D therapy should be prescribed alfacalcidol. Note One-Alpha® capsules contain sesame oil. Check summary of product characteristics for excipients of generic products.
Calcium and vitamin D supplements

First Choice:
Calcichew-D 3® Forte for osteoporosis
orCalcichew D 3® caplets
Dose
  • Calcichew–D3® Forte tablets (chewable) containing 500mg calcium and 400 units colecalciferol: 1 tablet twice daily.
  • Calcichew D3® caplets (swallowed whole) containing 500mg calcium and 400 units colecalciferol: 1 tablet twice daily.
Prescribing Notes
  • Calcichew–D3® Forte may be prescribed for osteoporosis. See section 6.6.

  • Calcichew–D3® Forte may be ineffective in moderate–severe renal disease; alfacalcidol may be a suitable alternative; see above.
  • Compliance with calcium and vitamin D preparations is often poor due to the unpleasant taste.  This should be monitored and, if patients cannot tolerate the first choice LJF preparation, other products with the same calcium and vitamin D dose may be tried

    ●  Adcal-D3® - chewable and dissolve
    ●  Calfovit D3® - sachets

9.6.5 Vitamin E

First Choice:
D-alpha tocopherol (Vita-E®)
Dose
  • Vita-E® 75iu capsules equivalent to 50mg of D-alpha tocopherol: 3 capsules daily with pancreatic enzymes.
Prescribing Notes
  • The 200iu capsules are blacklisted so funding will not be reimbursed where this is prescribed or supplied.
  • The maximum recommended dose of 400units daily should not be exceeded.
  • Levels are monitored once per year, compliance checked and dose adjusted at the cystic fibrosis clinic.
9.6.6 Vitamin K

Malabsorption syndromes (water–soluble preparation required)

First Choice:
menadiol sodium phosphate

Fat soluble formula (not malabsorption)

First Choice:
phytomenadione (vitamin K1)
Dose
  • menadiol sodium phosphate tablets equivalent to 10mg of menadiol phosphate: 10mg daily.
  • phytomenadione: see section 2.8.2 for use of phytomenadione to reverse the effects of warfarin.
Prescribing Notes
  • Menadiol sodium phosphate should be avoided in late pregnancy and labour unless benefit outweighs the risk of neonatal haemolytic anaemia, hyperbilirubinaemia and kerniticterus in neonate.
  • Konakion® MM Paediatric injection may also be administered by mouth.