Vitamin B6 (pyridoxal-5-phosphate, PLP) is a water-soluble vitamin essential for amino acid metabolism, neurotransmitter synthesis, and immune function. It is measured in serum to assess nutritional status and evaluate neurological or metabolic symptoms.
Vitamin B6 (pyridoxal-5-phosphate, PLP) is a water-soluble vitamin essential for amino acid metabolism, neurotransmitter synthesis, and immune function. It is measured in serum to assess nutritional status and evaluate neurological or metabolic symptoms.
When elevated: Elevated serum B6 levels are uncommon from dietary sources alone but can occur with excessive supplementation or certain medications. Chronically high levels have been associated with peripheral neuropathy and neurological toxicity, particularly at doses far exceeding recommended intake. When low: Low B6 status is associated with increased cardiovascular risk, impaired immune function, and neurological symptoms including peripheral neuropathy and cognitive changes. Deficiency may also elevate homocysteine levels, a cardiovascular risk factor.
B6 supports muscle protein synthesis and recovery by facilitating amino acid metabolism, particularly important during high training volumes. Athletes with inadequate intake or malabsorption may experience delayed recovery, reduced endurance capacity, or increased injury risk, making this marker relevant for those on restrictive diets or with persistent fatigue despite adequate training.
Turnaround Time
3 days (up to 9 days)
Method
Liquid chromatography-tandem mass spectrometry (LC/MS-MS)
verifiedGold StandardMass spectrometry — higher accuracy, especially at low concentrations
Order online
Choose your lab and check out. We send your lab requisition automatically — no doctor visit needed.
Get your sample collected
Visit a lab service center near you for a quick blood draw (or book at-home phlebotomy where available).
See your results
Your results land in your Insider portal, ready to review and act on — that easy.
Your price
$18.13$55
3.0× less than retail
Versus the typical direct-to-consumer retail price for this test (illustrative — consumer prices vary by provider and region).
$18.13
$37.90
Peer-reviewed sources supporting the educational content on this page.
Vitamin B6 (pyridoxal-5-phosphate, PLP) is a water-soluble vitamin essential for amino acid metabolism, neurotransmitter synthesis, and immune function. It is measured in serum to assess nutritional status and evaluate neurological or metabolic symptoms.
Vitamin B6 (pyridoxal-5-phosphate, PLP) is a water-soluble vitamin essential for amino acid metabolism, neurotransmitter synthesis, and immune function. It is measured in serum to assess nutritional status and evaluate neurological or metabolic symptoms.
When elevated: Elevated serum B6 levels are uncommon from dietary sources alone but can occur with excessive supplementation or certain medications. Chronically high levels have been associated with peripheral neuropathy and neurological toxicity, particularly at doses far exceeding recommended intake.
The Vitamin B6, Plasma test starts at $18.13 at Labcorp or Quest. No doctor's visit and no insurance needed; we do not bill insurance. Fitomics Insider members pay from $14.57.
Results for the Vitamin B6, Plasma test are typically ready about 3 days after your draw, and up to 9 days for some samples. Your results land in your Insider portal.
No. When you order the Vitamin B6, Plasma test from Fitomics Research Labs, a licensed physician in our 50-state network reviews and signs your requisition after checkout, and it lands in your portal and inbox. Then visit any Labcorp, Quest, or BioReference patient service center for your draw; results post to your Insider portal.
