Order Vitamin B6 (Pyridoxine) Blood Test from JustLabs for $39. Price includes lab processing at Quest Diagnostics. A one-time $18 collection fee applies per order. No insurance required.
Vitamin B6 is essential for over 100 enzyme reactions, particularly protein metabolism, neurotransmitter synthesis, immune function, and hemoglobin production.
Vitamin B6 (pyridoxine) is a water-soluble vitamin that serves as a cofactor for more than 100 enzymes involved in protein metabolism, red blood cell formation, and neurotransmitter synthesis. It's essential for producing serotonin, dopamine, and GABA—brain chemicals that regulate mood, sleep, and cognitive function.
B6 also plays crucial roles in immune function, hemoglobin synthesis (oxygen-carrying protein in blood), and converting stored glycogen to glucose for energy. It works closely with B12 and folate in homocysteine metabolism, and adequate B6 helps keep homocysteine levels in check.
While deficiency is relatively uncommon in people eating varied diets, certain populations are at risk, including older adults, people with autoimmune disorders, those with kidney disease, and individuals taking certain medications. Notably, B6 toxicity from excessive supplementation can cause peripheral neuropathy—a concern that makes testing valuable for those supplementing.
Price
$39
Results
3-5 business days
Lab Network
Quest
Fasting
Not Required
What's Measured
What This Test Measures
This test measures pyridoxal 5'-phosphate (PLP), the active form of vitamin B6, in your blood plasma. Normal levels typically range from 5-50 ng/mL. Levels below 5 ng/mL indicate deficiency, while chronically elevated levels from supplementation may cause toxicity.
Who Should Consider This Test
People with peripheral neuropathy symptoms, those taking high-dose B6 supplements (for nausea, PMS, carpal tunnel), individuals with autoimmune conditions (especially rheumatoid arthritis), people with kidney disease, older adults with poor nutrition, anyone with anemia not responding to iron, and those on medications that deplete B6.
Health Insights
Conditions Screened
Related Symptoms
When to Get Tested
No fasting required. B6 supplements should be stopped for 24-48 hours before testing for accurate baseline results. Inform your provider about all supplements you take.
Understanding Your Results
Normal B6 (PLP) is 5-50 ng/mL. Low levels indicate deficiency requiring supplementation and investigation of causes. Very low levels can cause anemia and neurological symptoms. High levels (>100 ng/mL) from chronic supplementation above 100mg/day can paradoxically cause sensory neuropathy.
What to Expect
After placing your order, you'll receive an email from Rupa Health (our lab order partner) within 24 business hours to sign a consent form and schedule your blood draw at a Quest Diagnostics location.
The blood draw typically takes just a few minutes. Results are usually available within 3-5 business days and will appear in your secure Justlabs dashboard.
Our results include reference ranges and easy-to-understand indicators showing whether your values are within normal limits.
Frequently Asked Questions
$39
Typical hospital cash price: $100–$200
+ $28 in standard lab & physician fees at checkout (no additional bills later)
$18 lab collection + $10 physician order
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