Vitamin D (25-hydroxy) level, prescribed analog measurement
This test measures the amount of vitamin D in your blood, which helps your body absorb calcium and maintain strong bones. Vitamin D is also important for muscle function and overall health.
Vitamin D supports bone health and muscle function, and low levels may affect overall well-being.
Key facts at a glance
- LOINC
- 72032-6
- Short code
- TYPENONORALVITAMINDANALOGPRESCRIBED
- Synonyms
- —
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Ref low
- 30
- Ref high
- 100
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- esrd
- CPT
- 86038
- Specimen volume
- 5 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–24 hours
- Order
- routine
Why Is This Test Done?
Your healthcare provider may order this test if you have symptoms like bone pain, muscle weakness, or fatigue. They might also recommend it if you have conditions like osteoporosis, rickets, or if you’re at higher risk for vitamin D deficiency due to limited sun exposure, certain medications, or dietary habits. Some people with chronic illnesses or those who don’t get enough sunlight are more likely to need this test.
What to Expect Before the Test
No special preparation is usually needed, but you may be asked to fast for 8–12 hours before the test if instructed by your provider. Bring any medications you’re currently taking, as some can affect results. If you’re pregnant or breastfeeding, let your healthcare provider know.
What Happens During the Test?
A healthcare professional will draw blood from a vein in your arm using a small needle. You may feel a brief pinch, but it usually doesn’t cause significant discomfort. The blood sample is then sent to a lab for analysis.
What Are the Results?
Results are typically reported as a concentration of vitamin D in your blood, measured in nanograms per milliliter (ng/mL). Your provider will interpret the results in relation to your health status and may recommend follow-up actions if levels are low or high.
Reference range
NCBI: Vitamin D 30-100 ng/mL (sufficient)N/A
Fasting for 8-12 hours preferred for some tests. Inform about supplements you are taking.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Low vitamin D levels can lead to bone-related issues like osteoporosis or rickets, especially in children. It may also contribute to muscle weakness, fatigue, or increased risk of certain infections. High levels can sometimes cause nausea, kidney stones, or other health concerns, though this is rare. Your provider will use the results to guide treatment, such as dietary changes, supplements, or increased sun exposure.
Short name
Vitamin D Blood Test
Frequently asked questions
How long does it take to get my test results?
Can I eat or drink anything before the blood draw?
Will I need to take any supplements after the test?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 17, 2026. · Read our editorial policy