Vitamin B6 levels: what's normal, high and low
A B vitamin involved in protein metabolism, neurotransmitter synthesis, and immune function.
Medically reviewed by Youmna DiStefano, MD · Last reviewed September 2026
The short answer
Vitamin B6 is measured with a standard blood draw; no fasting is needed. A typical reference range is 20.0 – 125 nmol/L. At TestWell it's $51.99 all-in as Vitamin B6 (Pyridoxine), results in 3–5 business days, drawn at Quest or Labcorp. An out-of-range result is a prompt to look closer, not a diagnosis.
- Units
- nmol/L / ng/mL
- Sample
- Blood draw
- Fasting
- Not required
- Results
- 3–5 business days
- Price
- $51.99
- Labs
- Quest or Labcorp
Vitamin B6 Reference Range
These are the typical adult reference ranges used by major US labs. Your report will include the specific range used by the lab that processed your sample.
| Population | Range |
|---|---|
| age 18+ | 20.0 – 125 nmol/L |
Reference ranges are educational. Always interpret your result with the specific range printed on your lab report and discuss anything outside the range with a clinician.
What your Vitamin B6 result may mean
Usually reflects supplement use. Excess can cause nerve damage at high doses.
What a high Vitamin B6 means: causes, symptoms, next steps →Can reflect alcohol use, certain medications, or absorption issues.
What a low Vitamin B6 means: causes, symptoms, next steps →Educational only — not a diagnosis. Many factors can influence a single result. Discuss anything that concerns you with a healthcare provider.
How do you get a Vitamin B6 test?
Order online, a licensed physician reviews the requisition, and you walk into a nearby lab for the draw. Vitamin B6 is available on its own or inside these panels — panels cost less per marker when you want the fuller picture.
| Option | Includes | Price |
|---|---|---|
| Vitamin B6 (Pyridoxine) | This marker only | $51.99 |
Quest vs. Labcorp for Vitamin B6: which lab should you pick?
Both are CLIA-certified national labs and the result is clinically equivalent, so pick whichever location is closer. Your report will print that lab's own reference range, which can differ slightly from the table above.
| Lab | Available | Price |
|---|---|---|
| Quest Diagnostics | Yes | $51.99 |
| Labcorp | Yes | $51.99 |
| BioReference (NY & NJ) | No | — |
Need help choosing a location? Use the lab finder to see draw sites near your ZIP.
Related Vitamins & Nutrients biomarkers
Markers commonly tested alongside Vitamin B6.
Frequently asked
Usually reflects supplement use. Excess can cause nerve damage at high doses. A single result above the reference range is a prompt to look closer with a clinician — often a repeat test and related markers — not a diagnosis on its own.
Ready to test your vitamin b6?
Order in two minutes, get physician-approved, and visit a lab the same day. Starts at $51.99.