Calcitriol (1,25 Dihydroxycholecalciferol) 💊

📚 Related Subjects: | Osteoporosis

📖 About

Always check the BNF link here before prescribing.

• 💊 Calcitriol = 1,25-dihydroxycholecalciferol.
• It is the active form of Vitamin D (does not require renal hydroxylation).

⚡ Mechanism of Action

• ⬆️ Increases intestinal absorption of calcium and phosphate.
• 🦴 Promotes bone mineralisation and reduces bone resorption.
• 🧬 Suppresses PTH secretion (useful in secondary hyperparathyroidism).

🩺 Indications

• Vitamin D deficiency, especially with renal impairment.
• Renal osteodystrophy (CKD-related bone disease).
• Postmenopausal osteoporosis (specialist use).

💊 Dose Calcitriol (1,25 Dihydroxycholecalciferol)

⚠️ Interactions

• See BNF for full list – interactions possible with enzyme inducers, diuretics, and calcium/phosphate supplements.

⚠️ Cautions

• Hypercalcaemia (monitor serum calcium regularly).
• Risk of metastatic calcification with prolonged high doses.
• Care in patients with renal stones or vascular calcification.

🚫 Contraindications

• See BNF – avoid in persistent hypercalcaemia or severe toxicity risk.

💥 Side Effects

• ⬆️ Hypercalcaemia → symptoms: nausea, vomiting, confusion, arrhythmias.
• 🪨 Nephrocalcinosis, renal stones.
• 🌡️ Rash, urticaria (rare).

📑 References

• BNF: Calcitriol