NSTK · 01.2026Independent supplement reference
NutriStack
Edition 1.0Updated August 1, 2026

Supplement × Prescription·Evidence index

Calcitriol and Vitamin D3: what the published research says

PubMed indexes 2 records that name Calcitriol and Vitamin D3 together, either in the title or in an interaction, co-administration, or pharmacokinetic context. Each one is listed below with its study design and, where the abstract states one, the authors’ own conclusion, quoted and linked. This page reports that literature. It does not tell you whether to combine them.

Read this first

An evidence index, not guidance.

Every statement below is attributed to a named, dated, linked source.

This page lists published research relevant to Calcitriol and Vitamin D3. It deliberately does not state whether the combination is safe, whether it interacts, in which direction, at what dose, or how far apart to take them.

The research

2 studies naming Calcitriol and Vitamin D3.

Strongest relevance first: papers naming both substances in the title, then human trials and systematic reviews.

Vitamin D supplementation: cholecalciferol, calcifediol, and calcitriol.

European journal of clinical nutrition · 2020 · PMID 32704098

ReviewHuman subjects

“Recent evidence shows that ergocalciferol is not stable with storage, and it is far more susceptible to breakdown with cooking and baking than is cholecalciferol. Therefore, it must be concluded that cholecalciferol is the only form of vitamin D that should be considered in the context of the nutritional functions of fortification and supplementation.”

Vieth · From the abstract

Names both Calcitriol and Vitamin D3 in its title.

Vitamin D supplementation and risk of stroke: A meta-analysis of randomized controlled trials.

Frontiers in neurology · 2022 · PMID 36062009

Systematic Review

“Our study revealed that additional vitamin D supplementation did not reduce the risk of stroke. Therefore, additional RCTs of similar design should not be encouraged to assess any association between vitamin D supplementation and reduced stroke risk.”

Fu et al. · Authors' conclusion

Names Calcitriol and Vitamin D3 together in an interaction, co-administration, or pharmacokinetic context.

Limitations

What this evidence cannot tell you.

Search-based evidence indexes have real limits, and it is worth being explicit about them:

NutriStack

Track what you actually take.

NutriStack is a free iPhone app for organising a supplement routine: what you take, when, and what the published record says about it. Its exploratory interaction checker covers Calcitriol, Vitamin D3, and several hundred other substances.

The checker is a research and organisation tool, not a clinical decision aid, and its per-pair assessments are excluded from search until they pass claim-level review.

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.