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Calcitriol - Learn about Calcitriol Side Effects and Precautions

Calcitriol Information

The pharmacology action of Calcitriol is that it supply of vitamin D depends mainly on exposure to ultraviolet rays of the sun for conversion of 7-dehydrocholesterol in the skin to vitamin D 3 (cholecalciferol). Vitamin D 3 is activated in the liver and kidney before fully active as a regulator of calcium and phosphorus metabolism at target tissues.

Calcitriol is used in treatment of secondary hyperparathyroidism and resultant metabolic bone disease in patients with moderate to severe chronic renal failure (Ccr 15 to 55 mL/min) not yet on dialysis.

Interaction and Contraindication of Calcitriol

Interaction of Calcitriol - Cholestyramine:  May reduce intestinal absorption of fat soluble vitamins.
Ketoconazole:  May reduce endogenous calcitriol concentrations.
Magnesium:  Magnesium-containing products may cause hypermagnesemia and should be avoided during calcitriol administration to patients on chronic renal dialysis.
Phenytoin/Phenobarbital:  Inhibits endogenous synthesis of calcitriol, therefore may require higher doses if given simultaneously.
Phosphate-binding agents:  Because phosphate transport in the intestine, kidneys, and bones may be affected, the dosage of phosphate-binding agents must be adjusted based on serum phosphate concentration.
Thiazides:  Known to induce hypercalcemia by the reduction of calcium excretion.
Vitamin D:  To avoid possible additive effects and hypercalcemia, withhold pharmacologic doses of vitamin D and its derivatives.

Contraindication of Calcitriol - Hypercalcemia or patients with vitamin D toxicity; hypersensitivity to any component of this product .

Side Effects of Calcitriol

Here are the list of some common side effects of Calcitriol :

Adverse effects are associated with excessive intake. The early stage of toxicity includes the following: weakness, headache, somnolence, nausea, vomiting, dry mouth, constipation, muscle pain, bone pain, metallic taste. The late stage symptoms of toxicity include the following: cardiac arrhythmias, hypertension, pruritus, conjunctivitis (calcific), anorexia, weight loss, pancreatitis, polyuria, polydipsia, nocturia, elevated BUN, nephrocalcinosis, hypercholesterolemia, elevated AST/ALT, albuminia, decreased libido, hyperthermia, photophobia, rhinorrhea, ectopic calcification, overt psychosis, dystrophy, sensory disturbances, dehydration, apathy, arrested growth, UTI.

Precaution and Warning while taking Calcitriol

The precaution and warnings of Calcitriol drug is as follows:

• Instruct patient to carefully follow the diet and calcium supplementation instructions supplied by health care provider.
• Advise patient to take prescribed dose without regard to meals but to take with food if GI upset occurs.
• Advise patient or caregiver using oral solution to use disposable graduated oral dispensers supplied with medication.
• Instruct dialysis patient to avoid using any magnesium-containing products (eg, antacids).
• Educate patient regarding signs and symptoms of hypercalcemia. Instruct patient to immediately inform health care provider if they occur.
• Advise women to notify health care provider if pregnant, planning to become pregnant, or breastfeeding.

How to store Calcitriol

• Administer prescribed dose without regard to meals, but administer with food if GI upset occurs.
• Administer dose in the morning to patient with hypoparathyroidism.
• Administer prescribed dose of oral solution using disposable graduated oral dispensers supplied with medication.
• Store capsules and oral solution at controlled room temperature (59° to 86°F). Protect from light.