Calcium 1000mg + Colecalciferol 800 units (Calcichew D3 Forte)

How it works

Colecalciferol is converted to active vitamin D metabolites that promote intestinal calcium absorption, while the supplied calcium provides substrate for bone mineralisation and helps suppress secondary hyperparathyroidism.

Prescribing in practice

• Avoid in hypercalcaemia, hypercalciuria and conditions predisposing to calcium-containing stones, and use caution in renal impairment and sarcoidosis where vitamin D sensitivity is increased.
• Separate administration from oral bisphosphonates, levothyroxine, iron and certain antibiotics, as the calcium reduces their absorption.
• Thiazide diuretics increase the risk of hypercalcaemia when combined.

Monitoring

Monitor serum and urinary calcium and renal function periodically, particularly in those with impaired renal function or on interacting drugs.

Counselling the patient

• Chew the tablet well; take it at a different time of day from a bisphosphonate, thyroid tablets or iron.
• Report symptoms such as nausea, constipation, excessive thirst or passing large amounts of urine, which may indicate high calcium.

Evidence & guidelines

Combined calcium and vitamin D supplementation is recommended adjunctive therapy in osteoporosis management, including in NICE fragility-fracture guidance.