Gen D3

Gen D3 (Vitamin D2) is a derivative of ergosterol formed by ultraviolet rays breaking of the C9-C10 bond. It differs from cholecalciferol in having a double bond between C22 and C23 and a methyl group at C24.

Gen D3 has an important role in energize the intestinal absorption for calcium and phosphor, to regulate their metabolism and balance in blood. It helps bone calcification. Deficiency of Gen D3 in the body causes deficiency of the calcium in the bone, weakness of its resistance and deformity.

Cholecalciferol is a Gen D3. Vitamin D is important for the absorption of calcium from the stomach and for the functioning of calcium in the body.

Cholecalciferol is used to treat or prevent many conditions caused by a lack of vitamin D, especially conditions of the skin or bones.

Cholecalciferol may also be used for purposes not listed in this medication guide.

1 tab daily.

See also:
What is the most important information I should know about Gen D3?

Contraindications for vitamin D analogues (Vitamin D2, Gen D3, Calcitriol, and Calcidiol)

Vitamin D should not be given to patients with hypercalcemia or evidence of vitamin D toxicity. Use of vitamin D in patients with known hypersensitivity to vitamin D (or drugs of the same class) or any of the inactive ingredients is contraindicated.

Gen D3 is used for the prevention and treatment of vitamin D deficiency. Gen D3 is important for absorption of calcium in the body. It is also used to prevent bone disorders such as osteomalacia and rickets.

See also:
What other drugs will affect Gen D3?

Interactions for vitamin D analogues (Vitamin D2, Gen D3, Calcitriol, and Calcidiol)

Cholestyramine

Cholestyramine has been reported to reduce intestinal absorption of fat soluble vitamins; as such it may impair intestinal absorption of any of vitamin D

Phenytoin/Phenobarbital

The coadministration of phenytoin or phenobarbital will not affect plasma concentrations of vitamin D, but may reduce endogenous plasma levels of calcitriol/ergocalcitriol by accelerating metabolism. Since blood level of calcitriol/ergocalcitriol will be reduced, higher doses of Rocaltrol may be necessary if these drugs are administered simultaneously

Thiazides

Thiazides are known to induce hypercalcemia by the reduction of calcium excretion in urine. Some reports have shown that the concomitant administration of thiazides with vitamin D causes hypercalcemia. Therefore, precaution should be taken when coadministration is necessary

Digitalis

Vitamin D dosage must be determined with care in patients undergoing treatment with digitalis, as hypercalcemia in such patients may precipitate cardiac arrhythmias

Ketoconazole

Ketoconazole may inhibit both synthetic and catabolic enzymes of vitamin D. Reductions in serum endogenous vitamin D concentrations have been observed following the administration of 300 mg/day to 1200 mg/day ketoconazole for a week to healthy men. However, in vivo drug interaction studies of ketoconazole with vitamin D have not been investigated

Corticosteroids

A relationship of functional antagonism exists between vitamin D analogues, which promote calcium absorption, and corticosteroids, which inhibit calcium absorption

Phosphate-Binding Agents

Since vitamin D also has an effect on phosphate transport in the intestine, kidneys and bones, the dosage of phosphate-binding agents must be adjusted in accordance with the serum phosphate concentration

Vitamin D

The coadministration of any of the vitamin D analogues should be avoided as this could create possible additive effects and hypercalcemia

Calcium Supplements

Uncontrolled intake of additional calcium-containing preparations should be avoided

Magnesium

Magnesium-containing preparations (eg, antacids) may cause hypermagnesemia and should therefore not be taken during therapy with vitamin D by patients on chronic renal dialysis.

See also:
What are the possible side effects of Gen D3?

Applies to cholecalciferol: oral capsule, oral capsule liquid filled, oral solution, oral tablet, oral tablet chewable, oral wafer

As well as its needed effects, cholecalciferol (the active ingredient contained in Gen D3) may cause unwanted side effects that require medical attention.

Major Side Effects

If any of the following side effects occur while taking cholecalciferol, check with your doctor immediately:

Incidence not known:

• Cough
• difficulty swallowing
• dizziness
• fast heartbeat
• hives or itching
• puffiness or swelling of the eyelids or around the eyes, face, lips, or tongue
• skin rash
• tightness in the chest
• unusual tiredness or weakness