Vitamin D2, A white crystalline compound produced by ultraviolet irradiation of ergosterol. Also called calciferol, ergocalciferol.
Vitamin D2 is much less effective than vitamin D3 in humans. Vitamin D2 is important for the absorption of calcium from the stomach and for the functioning of calcium in the body.
Ergocalciferol(vitamin D2), 9. 10-secoergosta-5,7,10(19),22-tetraen-3- 01,(3b,5Z,7E,22E)-, (C28H44O) with a molecular weight of 39665.
Ergocalciferol is a white, colorless crystal, insoluble in water, soluble in organic solvents, and slightly soluble in vegetable oils. It is affected by air and by light. Ergosterol or provitamin d2 is found in plants and yeast and has no antiarichitic activity.
Ergocalciferol (vitamin D2) is produced by ultraviolet irradiation of a provitamin D sterol (ergosterol) which occurs in yeast and fungi. Both of these agents which have equal biologic activity are metabolized in the liver to calcifediol (25-hydroxycholecalciferol) which is then hydroxylated in the kidney to calcitriol (1,25-dihydroxycholecalciferol). Calcitriol is considered the most active form. Dihydrotachysterol is produced by synthetic reduction of ergocalciferol. Patients with chronic renal disease cannot convert calcifediol to calcitriol. Alfacalcidol (1hydroxyvitamin D3), a synthetic analogue of calcitriol, is rapidly converted in the liver to calcitriol, bypassing the renal conversion step.
What should my health care professional know before I take vitamin D2?
They need to know if you have any of the following conditions:
.too much calcium or vitamin D in the blood
.other chronic illness
.an unusual or allergic reaction to vitamin D, other medicines, foods, dyes, or preservatives
.pregnant or trying to get pregnant
What if I miss a dose?
If you miss a dose, take vitamin D2 as soon as you can. If it is almost time for your next dose, take only that dose. Do not take double or extra doses.
What happens if I overdose?
Seek emergency medical attention.
Symptoms of a vitamin D2 overdose include irregular heartbeats, abdominal pain, nausea, vomiting, dry mouth, decreased appetite, constipation, weakness, headache, and a metallic taste in the mouth.
What drug(s) may interact with vitamin D2?
.seizure (convulsion) or epilepsy medicine
What side effects may I notice from taking vitamin D2?
The recommended daily allowance of vitamin D2 does not usually cause any side effects.
Early side effects related to overdose include:
.unusual tiredness, or weakness
Late side effects include:
.increase in the need to pass urine (especially at night)
.irregular heartbeat, high blood pressure
.loss of appetite