In the case of therapeutic treatment the dose should be established on an individual basis for the patients by regular checking of plasma calcium levels. During long-term treatment, serum calcium level, urinary calcium excretion and renal function should be monitored by measuring the serum creatinine level. Monitoring is especially important for elderly patients who concomitantly take cardiac glycosides or diuretics (see section 4.5), and in the case of hyperphosphataemia, as well as for patients with an increased risk of lithiasis. In case of hypercalciuria (exceeding 300 mg (7.5 mmol)/24 hours) or signs of impaired renal function the dose should be reduced or the treatment discontinued.
Renal impairment
Vitamin D should be used with caution in patients with impairment of renal function and the effect on calcium and phosphate levels should be monitored. The risk of soft tissue calcification should be taken into account. In patients with severe renal insufficiency, vitamin D in the form of colecalciferol is not metabolised normally and other forms of vitamin D should be used (see section 4.3, Contraindications).
Monitoring in children whose mother receives treatment with vitamin D
Similar monitoring is necessary for children whose mother receives treatment with vitamin D in pharmacological amounts. Some children may react with increased sensitivity to the effect of vitamin D.
Pseudohypoparathyroidism
Vitamin D3 capsules should not be taken if pseudohypoparathyroidism is present (the need for vitamin D may be reduced by the sometimes normal sensitivity to vitamin D, with a risk of long term overdose). In such cases, more manageable vitamin D derivatives are available.
Sarcoidosis
Colecalciferol should be prescribed with caution to patients suffering from sarcoidosis because of the risk of increased metabolism of vitamin D to its active form. These patients should be monitored with regard to the calcium content in serum and urine.
Use of additional supplements
Allowances should be made for vitamin D supplements from other sources. The concomitant use of multivitamin products and dietary supplements containing vitamin D should be avoided.
The need for additional calcium supplementation should be considered for individual patients. Calcium supplements should be given under close medical supervision.
Medical supervision is required whilst on treatment to prevent hypercalcaemia.
Paediatric population
Colecalciferol should not be given to children <12 years of age.
Sodium
This medicine contains less than 1 mmol sodium (23 mg) per 800 IU, that is to say essentially 'sodium-free'.