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evidence · mechanism · dose
Supplements/Vitamin

Vitamin D2 (Ergocalciferol)

Plant-derived prescription D — high doses (50,000 IU) used for rapid deficiency correction.

Bone HealthGeneral Wellness

Overview

Plant-derived prescription D — high doses (50,000 IU) used for rapid deficiency correction.

Natural sources
    Common forms

      Forms & variants of Vitamin D2 (Ergocalciferol)

      Different chemical forms of Vitamin D2 (Ergocalciferol) behave differently. Browse each form's mechanism, bioavailability, and best-use context.

      D3 (Cholecalciferol)
      Vitamin D3 (Cholecalciferol)

      Preferred form for raising 25(OH)D — the active form your skin makes from sun.

      Mechanism of action

      Same VDR endpoint as D3, but ~30% less effective at raising 25(OH)D per unit.

      Pathways

        Effects on the body

        Organ system effects

        Evidence-based benefits

        Corrects deficiency at high prescription dose

        Strong evidence

        Potential side effects

        Common
          Rare
            Serious
            • · Hypercalcemia (acute high-dose)

            Drug interactions

            No notable interactions reported.

            Supplement interactions

            Pairs well with

            None listed.

            Avoid combining with

            No specific avoidances listed.

            Dosing & bioavailability

            Typical dose
            50,000 IU weekly × 8 wk (Rx)
            With food?
            With fat

            Where to buy

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            Thorne
            Practitioner-grade · NSF tested

            Scientific evidence (8)

            Meta-analysisAm J Clin Nutr · 2012

            Vitamin D3 vs D2 in raising 25(OH)D

            Tripkovic L, et al.

            Meta-analysis comparing forms.

            Key findings

            D2 raises 25(OH)D less than D3 at equivalent doses.

            Open study
            Systematic reviewPubMed (NLM) · 1970

            PubMed: Vitamin D2 (Ergocalciferol) — Corrects deficiency at high prescription dose

            Live PubMed search

            Live results for "Vitamin D2 (Ergocalciferol) Corrects deficiency at high prescription dose" across the PubMed/MEDLINE peer-reviewed index.

            Key findings

            Opens current human and preclinical literature matching Vitamin D2 (Ergocalciferol) and "Corrects deficiency at high prescription dose". Filter by RCT, meta-analysis, or year on the results page.

            Open study
            Systematic reviewPubMed (NLM) · 1970

            PubMed: Vitamin D2 (Ergocalciferol) — randomized controlled trial

            Live PubMed search

            Live results for "Vitamin D2 (Ergocalciferol) randomized controlled trial" across the PubMed/MEDLINE peer-reviewed index.

            Key findings

            Opens current human and preclinical literature matching Vitamin D2 (Ergocalciferol) and "randomized controlled trial". Filter by RCT, meta-analysis, or year on the results page.

            Open study
            Systematic reviewPubMed (NLM) · 1970

            PubMed: Vitamin D2 (Ergocalciferol) — meta-analysis

            Live PubMed search

            Live results for "Vitamin D2 (Ergocalciferol) meta-analysis" across the PubMed/MEDLINE peer-reviewed index.

            Key findings

            Opens current human and preclinical literature matching Vitamin D2 (Ergocalciferol) and "meta-analysis". Filter by RCT, meta-analysis, or year on the results page.

            Open study
            Systematic reviewPubMed (NLM) · 1970

            PubMed: Vitamin D2 (Ergocalciferol) — pharmacokinetics

            Live PubMed search

            Live results for "Vitamin D2 (Ergocalciferol) pharmacokinetics" across the PubMed/MEDLINE peer-reviewed index.

            Key findings

            Opens current human and preclinical literature matching Vitamin D2 (Ergocalciferol) and "pharmacokinetics". Filter by RCT, meta-analysis, or year on the results page.

            Open study
            Systematic reviewPubMed (NLM) · 1970

            PubMed: Vitamin D2 (Ergocalciferol) — safety adverse events

            Live PubMed search

            Live results for "Vitamin D2 (Ergocalciferol) safety adverse events" across the PubMed/MEDLINE peer-reviewed index.

            Key findings

            Opens current human and preclinical literature matching Vitamin D2 (Ergocalciferol) and "safety adverse events". Filter by RCT, meta-analysis, or year on the results page.

            Open study
            Systematic reviewPubMed (NLM) · 1970

            PubMed: Vitamin D2 (Ergocalciferol) — dose response

            Live PubMed search

            Live results for "Vitamin D2 (Ergocalciferol) dose response" across the PubMed/MEDLINE peer-reviewed index.

            Key findings

            Opens current human and preclinical literature matching Vitamin D2 (Ergocalciferol) and "dose response". Filter by RCT, meta-analysis, or year on the results page.

            Open study
            Systematic reviewGoogle Scholar · 1970

            Google Scholar: Vitamin D2 (Ergocalciferol) — clinical evidence

            Live Scholar search

            Cross-database citation index for Vitamin D2 (Ergocalciferol) as it relates to "clinical evidence".

            Key findings

            Includes preprints, theses, and journal articles. Useful for tracking citation counts and follow-on work.

            Open study
            Educational use only. This profile is not medical advice. Consult a qualified healthcare professional before starting any supplement, especially if you take prescription medication or have a chronic condition.