Vitamin D Tablets 7000 Iu

Name of the medicine

Colecalciferol.

Excipients.

Soya oil, gelatin, glycerol, coconut oil - fractionated, black printing ink (Opacode S-1-17823).

Description

Chemical name: colecalciferol (5Z,7E)-9,10-secocholesta-5,7,10(19)-trien-3β-ol. CAS: 67-97-0. OsteVit-D One-A-Week capsules contain colecalciferol 175 microgram (equivalent to vitamin D3 7000 IU).
Inactive ingredients: soya oil, gelatin, glycerol, coconut oil - fractionated, black printing ink (Opacode S-1-17823).
This medicine is free from gluten, yeast, sugar or sweeteners, starch, lactose monohydrate and flavours.

Pharmacology

Colecalciferol, the natural form of vitamin D, is found in a limited range of foods (mainly milk and dairy products, fortified margarine, fatty fish and eggs). The major source of vitamin D in humans is formed through the action of ultraviolet light on 7-dehydrocholesterol in the skin to form provitamin D3 which is then converted to colecalciferol.

Pharmacodynamics.

Vitamin D is important in the regulation of calcium and phosphate metabolism and to optimise bone health and muscle function. Vitamin D deficiency causes secondary hyperparathyroidism which leads to cortical bone loss, osteoporosis and fractures. It may also cause fatigue, muscle weakness, increased body sway and falls.

Pharmacokinetics.

Absorption.

Colecalciferol is well absorbed from the gastrointestinal tract. Bile is essential for adequate intestinal absorption; therefore absorption may be decreased in patients with decreased fat absorption due to hepatic insufficiency. Patients with renal insufficiency will have decreased ability to form the active 1,25-dihydroxyvitamin D metabolite.

Distribution.

Vitamin D and its metabolites circulate in the blood bound to specific α-globulin. Vitamin D can be stored in adipose and muscle tissue for long periods of time. It is slowly released from such storage sites and from the skin. Colecalciferol has a slow onset and a long duration of action.

Metabolism.

Colecalciferol is hydroxylated in the liver by the enzyme vitamin D 25-hydroxylase to form 25-hydroxycolecalciferol (25 (OH)D). This compound undergoes further hydroxylation in the kidneys by the enzyme vitamin D 1-hydroxylase, under the influence of parathyroid hormone, to form the active metabolite 1,25-dihydroxycolecalciferol (calcitriol or 25 (OH)2 D). Further metabolism also occurs in the kidneys, including the formation of the 1,24,25-trihydroxy derivatives. Colecalciferol disappears from plasma with a half-life of 19 to 48 hours but is stored in fat deposits throughout the body for prolonged periods.

Excretion.

Excretion of vitamin D and its metabolites is mainly in the bile and faeces. Small amounts are eliminated in the urine. There is some enterohepatic recycling but it is considered to have a negligible contribution to vitamin D status. Vitamin D is also excreted in breast milk.
Its half-life has been estimated at between 15 and 50 days.

Bioavailability.

The effects of different excipients on the bioavailability of vitamin D supplements have not been thoroughly investigated in well designed clinical studies. Therefore no definite conclusions can be reached at this point.

Clinical Trials

The therapeutic basis for colecalciferol supplementation in the maintenance of vitamin D levels and for the prevention of vitamin D deficiency is well understood. The dosage for the preventative management of vitamin D deficiency is usually vit D3 1000 IU/day. There is inference from literature based data, summarised below, to permit flexibility in the dosing frequency e.g. vit D3 7000 IU/week, while still maintaining dosage at a daily average of vit D3 1000 IU.
One study with 48 women compared the efficacy of the same cumulative dose when given daily, weekly or monthly at 1500 IU, 10,500 IU or 45,000 IU respectively. There were increases in serum 25(OH)D levels in all groups, however there were no significant longer-term differences between the dosage regimens. The study concluded that the related dosing intervals can be selected freely to optimise an individual's adherence with long-term vitamin D supplementation.
338 male and female subjects participating in a randomised trial were given either 600 IU/day, 4200 IU/week, 18,000 IU/month or placebo. After 4 months, the mean serum 25(OH)D levels increased from a baseline of 25.0 nanomol/L to 62.5 nanomol/L (after daily vitamin D3 69.9 nanomol/L, weekly 67.2 nanomol/L and monthly 53.1 nanomol/L).
A double blind, placebo controlled trial with 226 male and female subjects investigated a weekly dose of 8400 IU against a placebo. Following 16 weeks of treatment, serum 25(OH)D concentrations rose significantly (from 13.9 to 26.2 nanogram/mL) in patients treated with 8400 IU vitamin D3, but not in the placebo treated group. The weekly dose of colecalciferol appeared to reach steady state after 8 weeks and was found to be well tolerated. The incidence of hypercalcaemia, hypercalciuria or kidney stones did not differ between the two groups and there were no laboratory, clinical or serious adverse events in the colecalciferol group.

Indications

For (a) the treatment of vitamin D deficiency in adults and adolescents as directed by your medical practitioner or pharmacist and (b) for the prevention of vitamin D deficiency in high risk individuals under the supervision of a medical practitioner or pharmacist.

Contraindications

Hypercalcaemia. Hypersensitivity to vitamin D or any of the excipients. Colecalciferol should not be used in patients with severe renal impairment.

Precautions

OsteVit-D One-A-Week should be given with care to patients with impaired renal function or calculi or heart disease who might be at increased risk of organ damage if hypercalcaemia occurred. Chronic hypercalcaemia can result in calcium deposits in many tissues, such as the arteries, kidneys and other soft tissue which may lead to hypertension and renal failure. Plasma phosphate concentrations should be controlled in these patients during vitamin D therapy to reduce the risk of ectopic calcification. Renal and cardiovascular damage may occur because of ectopic calcification.
Vitamin D3 may increase the magnitude of hypercalcemia and/or hypercalciuria when administered to patients with diseases associated with unregulated overproduction of calcitriol (e.g. leukaemia, lymphoma, sarcoidosis).
Urine and serum calcium, vitamin D and parathyroid hormone (PTH) levels should be monitored whilst taking OsteVit-D One-A-Week in order to assess the patients' response to treatment.
Avoid taking further medications including OTC and health food preparations that contain vitamin D.
Patients with malabsorption may not adequately absorb vitamin D3.

Effects on fertility.

No effects have been observed in reproductive fertility studies with colecalciferol.

Use in pregnancy.

Vitamin D3 is a therapeutic good which is exempted from pregnancy classification by TGA.
No data is available for colecalciferol, however, hypercalcaemia during pregnancy may produce congenital disorders in the offspring, and neonatal hypoparathyroidism. However, the risks to the foetus of untreated maternal hypoparathyroidism are considered greater than the risks of hypercalcaemia due to vitamin D therapy.

Use in lactation.

Vitamin D is distributed into breast milk, and its concentration appears to correlate with vitamin D levels in the serum of exclusively breastfed infants. The American Academy of Pediatrics considers the use of vitamin D to be usually compatible with breastfeeding, although they and others recommend that the infant be closely monitored for hypercalcaemia or clinical manifestations of vitamin D toxicity if the mother is receiving pharmacological doses of vitamin D.

Paediatric use.

OsteVit-D One-A-Week is not indicated for use in children under 12 years of age.

Use in the elderly.

OsteVit-D One-A-Week can be used in the elderly with caution due to the associated decrease in renal function.

Genotoxicity.

The genotoxicity of colecalciferol in humans has not been studied. Calcitriol, the hormonal metabolite of colecalciferol, has been found not to be genotoxic in the Ames microbial mutagenesis assay with or without metabolic activation, and in an in vivo micronucleus assay in mice.

Carcinogenicity.

The carcinogenic potential of colecalciferol in humans has not been studied.

Effects on laboratory tests.

Urinary calcium, phosphate, albumin, BUN, serum cholesterol, AST (SGOT) and ALT (SGPT) concentrations may increase.
Serum alkaline phosphatase concentrations may decrease.

Interactions

Orlistat, bile acid sequestrants (e.g. cholestyramine, colestipol), antacids, calcium and phosphate supplements may impair the absorption of vitamin D.
There is an increased risk of hypercalcaemia with thiazide diuretics, calcium or phosphate supplements.
Anticonvulsants, cimetidine and thiazides may increase the catabolism of vitamin D through P450 interactions.

Adverse Effects

Adverse reactions of vitamin D are rare and usually result from long-term intake at levels well above the current recommended dose of OsteVit-D One-A-Week.
Frequency category: uncommon (affecting ≥ 1/1000 and < 1 in 100 people), rare (affecting ≥ 1/10,000 and < 1/1000 people).

Metabolism and nutrition disorders.

Uncommon: hypercalcaemia, hypercalciuria.

Skin and subcutaneous disorders.

Rare: pruritus, rash, urticaria.

Dosage and Administration

Adults and children 12 years and over.

1 capsule once weekly as directed by your medical practitioner or pharmacist.
OsteVit-D One-A-Week can be taken with or without a meal.

Overdosage

Interindividual tolerance to vitamin D varies considerably; infants and children are generally more susceptible to its toxic effects.
Excessive intake of vitamin D leads to the development of hypercalcaemia and its associated effects including hypercalciuria, ectopic calcification, and renal and cardiovascular damage.
Symptoms of overdose may include anorexia, lassitude, nausea and vomiting, bone pain, weight loss, diarrhoea, polyuria, nocturia, sweating, headache, thirst, somnolence, constipation, muscle weakness, apathy, proteinuria, depression, vague aches, stiffness, anaemia, hypertension, cardiac arrhythmias, urinary tract infections and vertigo.
If symptoms arise, discontinue administration of vitamin D and give large quantities of fluids and electrolytes. The patient should be placed on a low calcium diet.

For vitamin D medicated hypercalcaemia.

Corticosteroids rapidly reduce hypercalcaemia in severe conditions. Oral sodium cellulose phosphate, which binds calcium in the GI tract, and a low calcium diet may also be considered. Oral chloroquine or hydroxychloroquine have been used in hypercalcaemia associated with sarcoidosis. Ketaconazole may be useful as an alternative to corticosteroids.
For information on the management of overdose, contact the Poisons Information Centre on 131 126 (Australia).

Presentation

OsteVit-D One-A-Week is a pale yellow transparent oil filled soft gelatin capsule with '7000' printed in black ink. Each OsteVit-D One-A-Week capsule contains 7000 IU (175 mcg) of colecalciferol and come in blister packs of 3, 5, 10, 15 , 20 and 30 capsules per carton for supply.

Note.

Not all pack sizes are currently being distributed in Australia.

Storage

Store below 25°C.

Poison Schedule

S3.

Vitamin D Tablets 7000 Iu

Source: https://www.nps.org.au/medicine-finder/oste-vit-d-one-a-week-capsules