Quick answer

Dekristol 20,000 IU is a prescription-only medicine containing 500 micrograms of cholecalciferol, prescribed as a weekly loading dose for a diagnosed vitamin D deficiency. Food supplements like our Vitamin D3 Depot (5,000 IU) are meant for general everyday intake; with a diagnosed deficiency the medical prescription remains decisive.

You can only get Dekristol 20,000 IU with a prescription – which is exactly why so many people search for a version they can buy freely. The honest answer: a food supplement doesn't replace this medicine, and that was never its job. Dekristol is prescribed for a diagnosed vitamin D deficiency, at a high dose, for a limited time. Here's what's actually in the capsules, why the dose is so high, how medicines and food supplements differ – and which path is right for whom.

What Dekristol 20,000 IU Is

Dekristol 20,000 IU soft capsules contain 500 micrograms of cholecalciferol per capsule – the chemical name for vitamin D3. 500 µg is equivalent to 20,000 international units (IU), the unit you'll see on most vitamin D products. Cholecalciferol is the same active ingredient found in food supplements too – the difference isn't the molecule, it's the amount, the approval status, and the intended use.

Dekristol 20,000 IU is a medicine, and at this strength it's prescription-only. You can only get it with a prescription from a pharmacy – not from a supermarket, a drugstore, or an unregulated online shop. It's approved for the initial treatment of clinically relevant vitamin D deficiency in adults – in other words, for situations where a blood test has already confirmed a deficiency that needs treating, not for preventive use on a hunch. It isn't intended for children under 12, and it isn't recommended for adolescents either. That makes Dekristol different from most over-the-counter products in two ways at once: not just the amount is higher, the purpose is different too – treatment, not everyday support.

Why It's Prescribed at This Strength

The high dose exists for a reason: to correct a confirmed deficiency within a manageable timeframe, not to maintain everyday levels. Doctors typically prescribe Dekristol 20,000 IU as a weekly dose – one capsule a week, for around four to five weeks. This so-called loading phase works because vitamin D is fat-soluble and gets stored in the body: a single high dose acts much like smaller amounts spread across several days, but it's easier to take and easier to monitor than a daily dose over weeks.

After the loading phase, the doctor rechecks your vitamin D blood level and decides from there whether – and at what lower dose – treatment continues. That close monitoring is exactly what sets a medicine apart from an over-the-counter product: the dose is guided by a measured value, not a blanket recommendation.

Medicine or Food Supplement — What Actually Differs

The fact that Dekristol needs a prescription and our vitamin D3 doesn't has nothing to do with quality – it comes down to legal classification, and it's worth understanding before you compare the two.

A medicine goes through an official approval process. The manufacturer has to prove efficacy, safety, and exact dosing before they're allowed to sell it – and the actual active-ingredient content is then only allowed to deviate from the label by a few percent. Its intended purpose is treating, relieving, or preventing a specific medical condition, in this case a diagnosed vitamin D deficiency.

A food supplement is legally classified as a food. It doesn't need approval, just a notification to the relevant food safety authority – a formal filing, not a review of its effects or safety. That makes the manufacturer solely responsible. Its intended purpose is narrowly defined: to supplement the normal diet of healthy people and support the maintenance of normal body functions – not to treat a medical condition. That's exactly why a food supplement never can, and never should, do what a prescribed medicine does: it's made for a different situation.

What the Reference Values Say

Three reference points help put the dosages in perspective – and they come from three different sources with three different purposes.

  • German Nutrition Society (DGE) estimated requirement: 20 micrograms (800 IU) a day – only for cases where the skin's own production is completely absent.
  • Analysis of adults (Ekwaru 2014): to reach a blood level of 100 nmol/l, about 2,080 IU a day were calculated at normal weight, about 3,065 at overweight and about 5,473 with obesity. Body weight clearly shifts the requirement.
  • Medical prescription: Dekristol 20,000 IU supplies 500 micrograms per capsule, as a weekly dose over about four to five weeks, followed by a check of the blood level.

Under normal circumstances, sunlight covers most of your requirement on its own; food only contributes 1 to 4 micrograms. So the DGE figure is a safety net for the darker months, not a baseline you need to hit year-round. Our Vitamin D3 Depot delivers 5,000 IU (125 µg) per tablet, taken once every 5 days – averaging out to around 1,000 IU (25 µg) a day, so more than the DGE estimated value. For comparison: 20,000 IU a week, as with Dekristol, averages around 2,860 IU a day. An investigation of 67 men in winter (Heaney 2003) estimated the daily use of healthy men at about 3,000 to 5,000 IU. Which amount suits you is shown by your blood level.

Which Path Is Right for Whom

If you've been prescribed Dekristol 20,000 IU, the answer is simple: keep taking it as agreed. A food supplement doesn't replace a prescribed medicine – ours included. If you want to change the dose, the product, or when to stop, talk to your doctor about it – not on your own, and not because a food supplement seems more convenient or cheaper.

If you have signs that could point to a deficiency – persistent tiredness through the darker months, say – or you belong to a higher-risk group, such as spending little time outdoors, having darker skin, or being older, a blood test at the doctor's is the right first step. It'll show whether a deficiency that actually needs treatment is present or not.

If you don't have a diagnosed deficiency and simply want to keep an eye on your baseline intake through the darker months, the food supplement aisle is the right place for you. That's exactly what our Vitamin D3 Depot with K2Pure® is designed for: a high-dose, everyday tablet with 5,000 IU every 5 days, combined with vitamin K2. Vitamin D contributes to the normal function of the immune system. Vitamin D contributes to the maintenance of normal bones. It's a supplement for general everyday intake – not a treatment, and not an alternative to a prescribed medicine. One more thing: preventive vitamin D intake in adults generally isn't covered by German statutory health insurance either way – another reason it's usually handled through over-the-counter products, while treating an already-diagnosed deficiency gets prescribed by a doctor.

What to Look for in a Vitamin D Supplement

A few criteria help you choose, regardless of the brand:

  • Vitamin D3, not D2: Cholecalciferol (D3) is the form your body makes itself, and it raises blood levels more reliably than D2.
  • Amount listed in micrograms: An IU figure on its own isn't legally sufficient – reputable brands always list the amount in µg too.
  • Independent lab testing: It shows whether the label actually matches what's inside – deviations aren't unusual in food supplements.
  • Paired with K2: Both vitamins contribute to the maintenance of normal bones.

Our Vitamin D3 Depot combines 5,000 IU of D3 with 100 µg of K2Pure®, a high-quality form of K2 (MK-7). Vitamin D contributes to the normal absorption and utilisation of calcium and phosphorus. The product is independently lab-tested, vegan, and made in Germany. This high-dose depot version isn't intended for pregnant or breastfeeding women, or for children and adolescents – that calls for separate guidance, usually from a doctor, anyway.

The Honest Take

What's well established: cholecalciferol is the same active ingredient either way – only the amount, the approval status, and the intended use differ. A diagnosed deficiency belongs in a doctor's hands, because that's where the dose gets guided by an actual measured value – something a food supplement can't and shouldn't attempt to do.

What we're not claiming: that a food supplement treats a deficiency or replaces a prescription. If you have been prescribed Dekristol, you stay with the medical prescription. If you want to keep an eye on your baseline intake without a deficiency being the issue, a lab-tested, high-dose food supplement like ours is a good fit.

Matching Products from Scheunengut

For general intake without a diagnosed deficiency: our Vitamin D3 Depot + K2Pure® is high-dose. It contains 5,000 IU (125 µg) vitamin D3 and 100 µg K2Pure® (MK-7) per tablet, just one every 5th day. 180 tablets last 900 days. Vegan, made in Germany, every batch independently lab-tested. Vitamin D contributes to the maintenance of normal bones. Vitamin D contributes to the normal function of the immune system. Vitamin D contributes to the maintenance of normal muscle function. Vitamin K contributes to the maintenance of normal bones. Not for pregnant or breastfeeding women, children and adolescents. Dekristol remains a medical prescription; whether and which product follows is something you decide with your doctor. Since 2012 we have worked without investors and with a focus on pure raw-material quality.

Frequently Asked Questions (FAQ)

Is Your Vitamin D3 Depot a Substitute for Dekristol 20,000 IU?

No. Dekristol 20,000 IU is a prescription-only medicine for treating a diagnosed deficiency; our depot is a high-dose food supplement for general everyday intake. If you've been prescribed Dekristol, keep taking it as agreed and discuss any changes with your doctor.

What's the Difference Between 20,000 IU and 5,000 IU?

20,000 IU equals 500 micrograms of cholecalciferol, 5,000 IU equals 125 micrograms – a quarter of the amount per capsule or tablet. Dekristol is prescribed as a weekly dose to correct a deficiency; our product is taken every 5 days for everyday intake, averaging around 1,000 IU a day.

How Do I Know If I Have a Vitamin D Deficiency?

Only a blood test at the doctor's, measuring your 25-OH-D level, can tell you for certain. Signs like persistent tiredness or low energy through the darker months can point to a deficiency, but they're not a diagnosis on their own – that takes the actual measurement.

Can I Just Switch From Dekristol to a Food Supplement?

That's not a decision to make on your own – it's one you make together with your doctor. After the loading phase, your blood level gets rechecked, and only then can anyone judge whether, and at what dose, treatment should continue – possibly with a lower-dose product.

Why Is Dekristol 20,000 IU Prescription-Only When Other Vitamin D Products Aren't?

Because the classification depends on amount and intended use. High-dose products for treating a diagnosed deficiency count as medicines; lower-dose products meant to supplement a normal diet count as food supplements. The active ingredient, cholecalciferol, is the same either way.

Who Actually Benefits From a Vitamin D Food Supplement?

People without a diagnosed deficiency who want some everyday support through the darker months – for example if you spend little time outdoors, have darker skin, or are older. If you actually suspect a deficiency, a blood test at the doctor's is still the better first step.

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Health notice: This guide is for general information purposes only and does not replace individual medical or pharmaceutical advice. Food supplements are not a substitute for a balanced, varied diet and a healthy lifestyle. If you have health concerns, are pregnant or breastfeeding, or are taking medication, please consult a doctor or pharmacist. How our guides are created →

Sources

  1. Dekristol® 20,000 IU Soft Capsules – Prescribing Information (SmPC) — Fachinfo.de (German Prescribing Information Register), 2024
  2. Reference Values for Nutrient Intake: Vitamin D — German Nutrition Society (DGE), 2012
  3. What Are Food Supplements, Legally Speaking? — German Consumer Advice Centre (Verbraucherzentrale), 2023
  4. The Importance of Body Weight for the Dose Response Relationship of Oral Vitamin D Supplementation and Serum 25-Hydroxyvitamin D in Healthy Volunteers — Ekwaru et al., PLOS ONE, 2014
  5. Human serum 25-hydroxycholecalciferol response to extended oral dosing with cholecalciferol — Heaney et al., American Journal of Clinical Nutrition, 2003
— Scheunengut Redaktion