Hidroferol Wöchentlich (Calcifediol Monohydrate)

Calcifediol monohydrate is a naturally occurring metabolite of vitamin D3 and is used primarily to support normal calcium and phosphate balance in the body.

• Supports maintenance of adequate serum 25‑hydroxyvitamin D concentrations
• May be considered in individuals with limited sunlight exposure
• Can be used as part of a nutritional regimen for bone health
• May assist in correcting mild vitamin D insufficiency identified by laboratory testing
• Provides a convenient weekly oral administration schedule
• Can be combined with calcium supplementation under professional guidance

• Calcifediol monohydrate is the 25‑hydroxylated form of vitamin D3. After oral absorption, it circulates bound to vitamin‑D‑binding protein and is converted in the kidneys to the active hormone calcitriol (1,25‑dihydroxyvitamin D). Both calcifediol and calcitriol bind the intracellular vitamin D receptor, modulating gene transcription that regulates calcium and phosphate absorption, bone remodeling, and immune function.

Adverse reactions to calcifediol are generally mild, but rare serious events have been reported.

Common

• Mild gastrointestinal discomfort (nausea, abdominal bloating)
• Transient headache
• Elevated serum calcium without symptoms
• Skin rash or mild itching

Serious

• Hypercalcemia with symptoms such as confusion, muscle weakness, or arrhythmia
• Severe allergic reaction (anaphylaxis, swelling of face or throat)
• Kidney stone formation

When using calcifediol, certain health conditions and situations require careful consideration to minimize risk.

• Do not use if known hypersensitivity to calcifediol or any excipients.
• Avoid use in uncontrolled hyperparathyroidism or active granulomatous disease.
• Exercise caution in patients with renal impairment or a history of kidney stones.
• Monitor serum calcium and 25‑hydroxyvitamin D levels during prolonged therapy.
• Pregnant or breastfeeding individuals should consult a healthcare professional before use.
• Elderly patients may be more susceptible to hypercalcemia and should be monitored.
• Concurrent use with high‑dose vitamin D supplements may increase risk of excess calcium.

Calcifediol can affect the activity of several medications, and some drugs may alter its metabolism or serum levels.

Avoid

• Concomitant use with thiazide diuretics in patients prone to hypercalcemia.
• High‑dose calcium supplements without medical supervision.
• Concurrent use with vitamin D analogues (e.g., calcitriol) unless directed by a clinician.

Use with caution

• Combined with glucocorticoids, as they may reduce vitamin D effectiveness.
• Combined with anticonvulsants such as phenytoin or phenobarbital, which can increase vitamin D catabolism.
• Combined with bisphosphonates, monitoring calcium status.
• Combined in patients receiving lithium, which can affect calcium metabolism.