1,25-Dihydroxyvitamin D2

ChemistryAlso known as: Vitamin d2, 1,25 (oh)2Also known as: 1,25-Dihydroxyergocalciferolng/dL

Measures the active form of vitamin D2 (ergocalciferol) in blood.

Normal Range
80 pg/mL
pg/mL
Abnormal Levels
< 0 ng/dL
> 4 ng/dL
Specimen Type
Blood

Why This Biomarker Matters

Active 1,25-D2 is potent at low levels. Elevations may indicate excessive supplementation, sarcoidosis, or lymphoma, requiring clinical investigation and management.

Understanding Your Results

Normal Range

80 pg/mL

Optimal Ranges

Clinician-defined 4-point reference thresholds (ng/dL)

Default Range

0
4
4
4
Low
0 ng/dL
Borderline Low
4 ng/dL
Optimal
4 ng/dL
Borderline High
4 ng/dL

Overview

1,25-dihydroxyvitamin D2 is the active, hormonally potent form of vitamin D derived from plant and fungal sources (ergocalciferol). A 1,25-D2 test measures this specific form, which is biologically active at very low concentrations. Elevated levels may indicate excessive supplementation, granulomatous diseases (like sarcoidosis), or lymphomas that abnormally produce this hormone. This test is more specialized than standard vitamin D testing and is useful for investigating specific clinical conditions.

Technical Information (LOINC Codes)

Standardized laboratory codes for this biomarker

62291-0Primary
1,25-Dihydroxyvitamin D2 [Mass/volume] in Serum or Plasma
pg/mL

Available Lab Tests

Order tests that measure this biomarker

Vitamin D 1 25 Dihydroxy Test

$79.09