Vitamin B6

Also known as: pyridoxine, pyridoxal-5-phosphate, p5p, b6

Grade A — Strong Evidencevitaminfoundationalneurological
1050 mgMorning with food

Essential coenzyme for neurotransmitter synthesis (serotonin, GABA, dopamine). Strong evidence for PMS. Deficiency common in those on OCP or with poor diet.

Last reviewed: 2026-03-11

Evidence

Grade A

Studies

2

Interactions

2

Forms

1

Evidence Rating: Grade A — Strong Evidence

Multiple high-quality RCTs, systematic reviews, or meta-analyses with consistent findings.

Interaction Warnings

Levodopa (L-DOPA)High Risk

B6 accelerates peripheral conversion of levodopa, reducing brain availability. Contraindicated without carbidopa.

Phenobarbital/PhenytoinModerate

B6 may reduce anticonvulsant blood levels.

⚠️ Important Notes

  • Doses >200mg/day long-term associated with sensory neuropathy
  • P5P (pyridoxal-5-phosphate) is the active coenzyme form — preferred over pyridoxine HCl for high doses
  • Most people get adequate B6 from diet unless on oral contraceptives or isoniazid

Clinical Evidence (2 studies)

Vitamin B6 supplementation and PMS: RCT meta-analysis

Wyatt KM et al. (1999) — BMJ

B6 up to 100mg/day likely beneficial for PMS symptoms and premenstrual depression

View on PubMed

B6 and cognitive function in the elderly

Dakshinamurti K et al. (1990) — Ann N Y Acad Sci

B6 deficiency impairs cognitive function; supplementation in deficient elderly improves memory

View on PubMed

Alternatives to Consider

These supplements target similar goals and may be worth considering alongside or instead of Vitamin B6.

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⚕️ Important Disclaimer

This information is for educational purposes only. It is not medical advice. Always consult a healthcare provider before starting any supplement regimen, especially if you take medications or have health conditions.

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