Overview

Vitamin B6 comprises pyridoxine, pyridoxal, and pyridoxamine. Pyridoxal 5-prime-phosphate is the principal active coenzyme. See Vitamin B6 and B-complex vitamins.

Mechanism

PLP supports transamination, decarboxylation, one-carbon metabolism, heme synthesis, glycogen breakdown, and neurotransmitter production.

Uses

Vitamin B6 is used to prevent or treat deficiency and is prescribed in selected metabolic conditions. It may be used with isoniazid under medical guidance to reduce deficiency risk.

Dosage

Adult reference intake is roughly 1.3–1.7 mg/day, varying with age and sex. Chronic high-dose supplementation can cause neuropathy; use the lowest appropriate dose and follow local upper-limit guidance.

Adverse effects

Long-term excess can cause sensory neuropathy, numbness, or gait problems. Interactions and total intake from multiple products should be reviewed by a clinician.

Claims and evidence

Deficiency correction is established. Evidence for high-dose B6 for mood, energy, or premenstrual symptoms is condition-specific and does not justify indiscriminate high dosing.

Research

Research addresses homocysteine metabolism, neurobiology, pregnancy, inflammatory disease, and biomarkers of B6 status.