nutrient

Pyridoxal 5′-phosphate

A phosphorylated, coenzyme form of vitamin B6 used by many enzymes.

Pyridoxal phosphate is made and regulated in tissues; foods and products may provide different B6 vitamers.

What the form means

Pyridoxal 5′-phosphate supports amino-acid, neurotransmitter and haem metabolism as an enzyme cofactor.

Forms

  • Pyridoxal 5′-phosphate is a form of Vitamin B6.

    Pyridoxal 5′-phosphate is a named chemical form within its parent vitamin family.

Worth knowing

  • A working B6 coenzyme. Pyridoxal 5′-phosphate, or PLP, is an active vitamin B6 coenzyme used by enzymes involved in amino-acid metabolism and neurotransmitter and haem production.

A closer look

Why blood tests measure PLP

Plasma PLP is the most common measure of vitamin B6 status, even though the diet can provide several B6 vitamers. A PLP result therefore describes body status at the time of testing; it does not identify which food or supplement form supplied the vitamin.

References

Source-checked local draft.
Human editorial review pending.

  1. NIH Office of Dietary SupplementsVitamin B6: Fact Sheet for Health ProfessionalsChecked 2026-09-05