Supplement × Prescription·contraindicated·Strong evidence
Additional vitamin D can increase the risk of vitamin D toxicity and hypercalcemia during calcitriol therapy.
Every entry follows the same shape: what is happening, the mechanism, and the recommendation.
What is happening. Additional vitamin D can increase the risk of vitamin D toxicity and hypercalcemia during calcitriol therapy.
Mechanism. Overlapping vitamin D receptor activation and increased calcium and phosphate absorption.
Recommendation. Do not add vitamin D supplements unless the prescriber specifically orders them and monitors calcium and vitamin D status.
Effect on the composite score
If both Calcitriol and Vitamin D3 are in the same stack, this pair applies −25 to your Stack Score (per scored contraindication row).
The full algorithm, the clamping rules, and four worked stacks are at /methodology/stack-score.
Every claim on this page is cited. PMIDs link straight to PubMed.
Check your full routine
Drop your supplements and prescriptions into NutriStack and it runs every pair at once: every interaction, synergy, timing rule, and contraindication, each linked to its primary source.
NutriStack is an informational and organizational tool, not a medical service, and not a substitute for professional advice. Always consult a qualified healthcare professional before starting, stopping, or changing any supplement or medication.
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