Hidroferol Wöchentlich (Calcifediol Monohydrate)

Hidroferol Wöchentlich is indicated for the correction of vitamin D deficiency and for the maintenance of sufficient 25‑hydroxyvitamin D concentrations in people at risk of low levels.

• Adults with documented vitamin D deficiency.
• Individuals with limited sun exposure.
• Patients with malabsorption conditions that affect vitamin D.
• Elderly persons prone to osteomalacia or fractures.
• People on medications that increase vitamin D catabolism.
• Patients with chronic kidney disease stages 3–4 where calcifediol may be preferred.

• Calcifediol monohydrate is the 25‑hydroxylated form of vitamin D3. After oral absorption, it is directly converted to 25‑hydroxyvitamin D in the circulation, bypassing hepatic 25‑hydroxylation. The resulting 25‑hydroxyvitamin D binds to the vitamin D receptor (VDR) in target tissues, regulating gene transcription that promotes intestinal calcium and phosphate absorption and supports bone mineralization. It also modulates immune function and influences parathyroid hormone secretion, contributing to overall calcium homeostasis.

Adverse reactions to Hidroferol Wöchentlich are generally uncommon, but they can occur. Reported events are grouped by frequency and clinical significance.

Common

• Mild gastrointestinal discomfort such as nausea or abdominal bloating.
• Transient headache.
• Slight increase in serum calcium without symptoms.
• Fatigue or generalized weakness.

Serious

• Hypercalcemia presenting with polyuria, polydipsia, or cardiac arrhythmia.
• Allergic skin reactions including rash or urticaria.
• Acute kidney injury related to severe hypercalcemia.
• Calcific deposits in soft tissues (rare).

Before using Hidroferol Wöchentlich, certain conditions and circumstances should be considered to minimize risk.

• Assess baseline serum calcium and 25‑hydroxyvitamin D levels.
• Avoid use in patients with known hypercalcemia or hyperparathyroidism.
• Use cautiously in individuals with renal impairment, especially stage 3 or higher.
• Monitor elderly patients for signs of excessive calcium accumulation.
• Discuss with a healthcare professional if taking medications that affect vitamin D metabolism.
• Pregnant or breastfeeding women should seek medical advice, as safety data are limited.

Calcifediol can affect or be affected by several other agents; awareness of these interactions helps ensure safe use.

Avoid

• Concomitant high‑dose vitamin D supplements that may cause hypercalcemia.
• Thiazide diuretics, which reduce renal calcium excretion and increase hypercalcemia risk.

Use with caution

• Corticosteroids, which can lower vitamin D effectiveness.
• Anticonvulsants such as phenytoin or phenobarbital that increase vitamin D catabolism.
• Bisphosphonates, where calcium balance should be closely monitored.