Seeking Health P-5-P (Pyridoxal 5-Phosphate) provides vitamin B6 in its active coenzyme form — directly usable by the body without conversion. P5P is a critical cofactor for over 100 enzyme reactions including neurotransmitter synthesis, histamine breakdown, methylation and amino acid metabolism.

Frequently Asked Questions

What is P-5-P and how does it differ from regular B6?

Pyridoxal 5-phosphate (P5P) is the active coenzyme form of vitamin B6. Regular B6 supplements (pyridoxine) require liver conversion to P5P before use. Those with liver conditions or genetic variants impairing conversion benefit most from direct P5P supplementation.

Why is P5P important for histamine intolerance?

P5P is an essential cofactor for the DAO enzyme that breaks down histamine. Insufficient P5P impairs DAO activity, contributing to histamine accumulation. P5P also supports HNMT (breaks down histamine in tissues) and COMT and MAO enzymes involved in neurotransmitter metabolism.

What other roles does P5P play?

P5P is a cofactor for over 100 enzymes including those involved in serotonin, dopamine and GABA synthesis, glycine and taurine production, haem (red blood cell) synthesis, gluconeogenesis and amino acid transamination.

How should I take P-5-P?

Take as directed by your healthcare professional. P5P is often used in combination with other B vitamins. Always use at recommended doses — high long-term doses of B6 can cause peripheral neuropathy, though this is less of a concern with P5P than pyridoxine.