Vitamin D 1 25-Dihydroxy Test
Short Name: Vitamin D 1,25 Dihydroxy (Calcitriol)
Also known as: Calcitriol Test, 1,25-Dihydroxyvitamin D Test, 1,25(OH)2D
Vitamin D 1 25-Dihydroxy Test test available at DNA Labs India for ₹4,500. Uses CLIA (Chemiluminescent Immunoassay) on Serum samples. Results in Reports are typically delivered on the same day if the sample is collected before 11 AM. For samples collected later, reports may be available by the next day.. Free home collection in 300+ cities across India.
🩺 Medically Reviewed By
Dr Ramarao Paidisetty
Consultant Biochemist · Reg: 21504
Last reviewed: September 7, 2026
Overview
The Vitamin D 1,25-Dihydroxy Test is primarily done to evaluate active vitamin D levels in patients with calcium or phosphate abnormalities, suspected deficiency despite normal 25-hydroxy levels, or conditions affecting vitamin D activation. It helps diagnose vitamin D deficiency and also aids in investigating hypercalcemia associated with conditions like sarcoidosis and other granulomatous disorders where unregulated production of 1,25-dihydroxy vitamin D occurs. The test is also used to monitor therapy in patients with rickets or osteomalacia, and to assess renal production of active vitamin D in kidney disease.
- Test Code
- 3735
- Price
- ₹4,500
- Sample Type
- Serum
- Result Time
- Reports are typically delivered on the same day if the sample is collected before 11 AM. For samples collected later, reports may be available by the next day.
- Fasting Required
- No
- Method
- CLIA (Chemiluminescent Immunoassay)
Sample Collection
No special preparation is required. You may eat and drink normally unless your physician advises otherwise.
Method: Blood Draw
Laboratory Analysis
A blood sample is collected from a vein in your arm using a sterile needle. The procedure takes less than 5 minutes.
Report Delivery
You may resume normal activities immediately. A small bruise or soreness at the puncture site is possible but resolves quickly.
Timeline: Reports are typically delivered on the same day if the sample is collected before 11 AM. For samples collected later, reports may be available by the next day.
Patient Instructions
About This Test
Who Should Get This Test
The Vitamin D 1,25-Dihydroxy Test is primarily done to evaluate active vitamin D levels in patients with calcium or phosphate abnormalities, suspected deficiency despite normal 25-hydroxy levels, or conditions affecting vitamin D activation. It helps diagnose vitamin D deficiency and also aids in investigating hypercalcemia associated with conditions like sarcoidosis and other granulomatous disorders where unregulated production of 1,25-dihydroxy vitamin D occurs. The test is also used to monitor therapy in patients with rickets or osteomalacia, and to assess renal production of active vitamin D in kidney disease.
How to Prepare
- No fasting required
- Inform your doctor about any supplements or medications you are taking
- Wear a short-sleeved shirt or loose sleeve for easy access to the arm
- Let the phlebotomist know if you have a history of fainting or bleeding disorders
Doctor's Notes
Reviewed by Dr Ramarao Paidisetty — MBBS, MD (Biochemistry) · Reg. No. 21504
"1,25-dihydroxy vitamin D testing is crucial when calcium or phosphate abnormalities are present alongside suspected vitamin D metabolism disorders. Unlike 25-hydroxy vitamin D, this test evaluates the active hormonal form and helps differentiate renal or granulomatous causes of hypercalcemia."
Last medically reviewed: September 7, 2026
Test Parameters & Specifications
Sample Stability
- Hemolyzed or lipemic sample
- Improperly labelled specimen
- Sample received after the stability time
- Non-serum sample (plasma or whole blood)
Understanding Your Results
Low 1,25(OH)2D (<20 pg/mL) with normal 25(OH)D
Impaired conversion to active form, often due to chronic kidney disease or hypoparathyroidism
Low 1,25(OH)2D with low 25(OH)D
True vitamin D deficiency with reduced active form
High 1,25(OH)2D (>60 pg/mL) with hypercalcemia and low PTH
Possible granulomatous disease, lymphoma, or vitamin D intoxication
High 1,25(OH)2D with high PTH
Secondary hyperparathyroidism with increased conversion
Consult your physician if you experience persistent fatigue, bone pain, muscle weakness, unexplained fractures, or symptoms suggestive of calcium imbalance such as nausea, vomiting, confusion, or excessive thirst. Also consult if you have a chronic condition like kidney disease, sarcoidosis, or hyperparathyroidism that warrants monitoring of vitamin D metabolism.
Limitations
- ⚠This test is not a first-line screening test for vitamin D deficiency; 25-hydroxy vitamin D is preferred for initial evaluation
- ⚠1,25-dihydroxy vitamin D levels are tightly regulated and may remain normal even with significant total body vitamin D deficiency
- ⚠The test reflects a snapshot and may vary with time, hydration status, and circadian rhythm
- ⚠Results must be interpreted in conjunction with calcium, phosphate, and PTH levels
- ⚠Assay may not differentiate between D2 and D3 forms in all methods, though CLIA measures both
Risks & Considerations
- ●Slight pain or stinging during blood draw
- ●Minor bruising at the puncture site
- ●Rare risk of infection, bleeding, or hematoma
Interfering Factors
- ●Recent intake of vitamin D supplements, including calcium-vitamin D combinations
- ●Kidney disease or medications affecting vitamin D metabolism such as corticosteroids or anticonvulsants
- ●Pregnancy, as 1,25-dihydroxy vitamin D levels normally rise
- ●Recent surgery or severe medical illness may transiently alter levels
- ●Blood sample must not be hemolyzed or lipemic as it may affect assay accuracy
Compare With Similar Tests
| Test | Vitamin D 1 25-Dihydroxy Test | ||
|---|---|---|---|
| Comparison | Vitamin D 1 25-Dihydroxy Test |
Frequently Asked Questions
What is the Vitamin D 1,25-Dihydroxy Test?
What is the difference between 25-hydroxy and 1,25-dihydroxy vitamin D?
Is fasting required for this test?
What is the cost of the Vitamin D 1,25-Dihydroxy Test?
How long does it take to get the report?
What does a high 1,25-dihydroxy vitamin D level mean?
What does a low 1,25-dihydroxy vitamin D level mean?
Who should get this test?
Can I take vitamin D supplements before the test?
Is home collection available for this test?
Which conditions can cause elevated 1,25-dihydroxy vitamin D?
How is this test performed?
Related Tests
Reference Laboratory Services
We serve as a reference laboratory for hospitals and clinics across India. Send samples from your facility with same-day pickup, priority processing, and results delivered through our online portal. Competitive institutional pricing available.
Your Data Privacy
Your medical data is protected under Indian law.
✓ Stored in India: All patient records are stored on servers located in India. No data is transferred outside the country.
✓ DPDP Act Compliant: Under the Digital Personal Data Protection Act 2023, you can request deletion of your records at any time by contacting support.
Book Your Test
Enter your details and we'll connect you within 15 minutes.