Neurotransmitter synthesis
Essential for serotonin, dopamine, and GABA production
Vitamin B6 (P5P)
Active coenzyme form of vitamin B6 essential for amino acid metabolism, neurotransmitter synthesis, and hormone regulation
Scientific namePyridoxal 5'-Phosphate
FormulaC8H10NO6P
Molecular weight247.14 g/mol
CAS54-47-7
90
absorption score
8
safety / 10
18
USD per month
5
documented interactions
Check it against something
Vitamin B6 (P5P) with:
- Amylase
- Ashwagandha
- Avocado Oil
- BCAA (Branched-Chain Amino Acids)
- Beetroot Powder
- Beta-Alanine
- Bifidobacterium lactis
- Bifidobacterium longum
- Bovine Collagen
- Caffeine
- Calcium
- Calcium Bone Formula
- Calcium Carbonate
- Casein Protein
- Chicken Collagen
- Choline (Bitartrate)
- Chondroitin Sulfate
- Coconut Oil
- Collagen Peptides
- Comprehensive Immune Support Complex
- Comprehensive Multivitamin-Mineral Complex
- Creatine HCL
- Creatine Monohydrate
- D-Mannose
- DHA
- Electrolyte Blend
- EPA
- Fish Oil (EPA/DHA)
- Folate (5-MTHF)
- Ginger
- Iron Fumarate
- Iron Sulfate
- Joint Mobility Formula
- Keratin
- Krill Oil
- L-Carnitine
- L-Citrulline
- Lactase
- Lactobacillus acidophilus
- Lactobacillus rhamnosus
- Lipase
- Magnesium Citrate
- Magnesium Glycinate
- Magnesium Oxide
- Marine Collagen
- Melatonin
- Modafinil
- Olive Oil Extract
- Omega-3 + Curcumin + Vitamin D Triple Anti-Inflammatory Formula
- Papain
- Protease
- Saccharomyces boulardii
- Turmeric
- Vitamin B12 (Cyanocobalamin)
- Vitamin B12 (Methylcobalamin)
- Vitamin C (Ascorbic Acid)
- Vitamin C (Sodium Ascorbate)
- Vitamin D3
- Whey Protein
- Zinc Gluconate
Nothing found
99
out of 100
Works better together
Compatible. Timing differs, so follow each supplement's own window.
What it does
mechanism and evidence for each claimPMS and hormonal support
May reduce PMS symptoms by 50-70%
Amino acid metabolism
Essential for protein utilization and muscle building
Cardiovascular health
Helps maintain healthy homocysteine levels
Immune function
Supports antibody production and lymphocyte function
Others take these for the same thing
Same goal, different mechanism — check any of them against this one
Melatonin
Sleep support & circadian rhythm
0.5-3mg
A
50%
Vitamin B12 (Cyanocobalamin)
Energy & nerve support
250-1000 mcg
A
70%
Fish Oil (EPA/DHA)
Heart & brain health
1-2g EPA/DHA
A
85%
L-Theanine
Calm focus & stress relief
100-400mg
B
90%
Vitamin B8 (Inositol)
Mental health & PCOS support
2-18g (condition dependent)
B
95%
Boron - Essential Trace Mineral for Bone and Hormone Health
Bone health & hormone support
3-10mg daily
B
85%
Every pair we checked
12 combinations scored by the engine
Vitamin B6 (P5P) + Caffeine
No documented interaction either way
No known interaction
70
Vitamin B6 (P5P) + Creatine Monohydrate
No documented interaction either way
No known interaction
70
Vitamin B6 (P5P) + Whey Protein
No documented interaction either way
No known interaction
70
Vitamin B6 (P5P) + Turmeric
No documented interaction either way
No known interaction
70
Vitamin B6 (P5P) + Vitamin D3
Large doses of pyridoxine may compete with P5P
Needs attention
78
Vitamin B6 (P5P) + Vitamin C (Ascorbic Acid)
Large doses of pyridoxine may compete with P5P
Needs attention
82
Vitamin B6 (P5P) + Lactase
Improved calcium absorption when consuming dairy
Works better together
82
Vitamin B6 (P5P) + Bovine Collagen
Essential for collagen synthesis and cross-linking
Works better together
82
Vitamin B6 (P5P) + DHA
Prevents oxidation of DHA and enhances stability
Works better together
82
Vitamin B6 (P5P) + Magnesium Oxide
Required for P5P enzyme function
Works better together
94
Vitamin B6 (P5P) + Calcium Carbonate
Essential for calcium absorption and utilization
Works better together
94
Vitamin B6 (P5P) + Zinc Gluconate
Works together in amino acid metabolism
Works better together
99
Dosage
Daily25-100 mg
Maintenance10-25 mg
Therapeutic50-200 mg
Maximum100 mg (tolerable upper limit)
ToxicAbove 200 mg daily long-term
Upper limit
100 mg NIH ODS
Before you take it
VeganYes
When to expect it
First Effects1-2 weeks for amino acid metabolism improvements
Peak Benefits4-8 weeks for neurotransmitter and hormonal benefits
Deficiency Development2-6 weeks with inadequate intake
Toxicity OnsetMonths of very high doses (>200mg daily)
How to measure it
MarkerPlasma P5P
Optimal20-121 nmol/L
Deficient below20 nmol/L
FrequencyOnly if deficiency suspected or high-dose supplementation
What people actually reported to the FDA
CAERS, 78 reports naming it as the suspectMost reported effects
Named as the suspect
78 reports
of 176 that mention it at all
Serious outcome
90%
hospitalisation, emergency room or worse
Other Serious or Important Medical Event58
Disability28
Hospitalization10
Reports are voluntary and unverified — they record what someone experienced while taking something, not what the compound caused. Counts skew towards products people take a lot of, and a serious outcome is more likely to be reported than a mild one, so these are not rates. How we filter them →
What actually reaches you
The label counts the carrier, your body does not
Absorption
Very high 90 of 100 · best absorbed form of this compound
Delivered daily
56.3 mg
Cost per 100 mg delivered
$1.07 comparative — uses the absorption score, not a measured percentage
Works better with
+
Magnesium
Required for P5P enzyme function
Cofactor for many P5P-dependent enzymes · level A
+
Zinc
Works together in amino acid metabolism
Both required for protein synthesis pathways · level B
+
Vitamin B2
Required for B6 metabolism and activation
Needed for converting pyridoxine to P5P · level AWhat not to take with Vitamin B6 (P5P)
!
Alcohol
Increases B6 requirements and depletion
Interferes with P5P formation and increases excretion · moderate significance
!
Pyridoxine Excess
Large doses of pyridoxine may compete with P5P
Competitive inhibition at enzyme binding sites · controversial significanceMedication interactions
Discuss these with a pharmacist before combiningB6 may reduce levodopa effectiveness
What to do: Avoid B6 supplements or use carbidopa combination
Isoniazid depletes B6 and may cause neuropathy
What to do: Prophylactic B6 supplementation recommended
Birth control pills deplete B6 levels
What to do: Consider B6 supplementation
Available forms
Pyridoxal 5'-Phosphate (P5P): Active form, No conversion required, Better for some individuals
Pyridoxine HCl: Less expensive, More stable, Most research
Pyridoxamine: Natural form, Good absorption, Additional benefits
Food sources
Chickpeas
1.1 mg/100g · 75
Tuna
1.0 mg/100g · 80
Salmon
0.8 mg/100g · 80
Chicken breast
0.5 mg/100g · 75
Potatoes
0.3 mg/100g · 70
Too little
- Depression and irritability
- Confusion and cognitive problems
- Peripheral neuropathy
- Seborrheic dermatitis
- Anemia (microcytic)
- Weakened immune function
- Increased PMS symptoms
Too much
- Peripheral neuropathy (nerve damage)
- Numbness and tingling in extremities
- Loss of muscle coordination
- Photosensitivity
- Nausea at very high doses
- Skin lesions (rare)
Who benefits most
women-with-pms
B6 significantly reduces PMS symptoms
50-100 mg daily
birth-control-users
Oral contraceptives deplete B6 levels
25-50 mg daily
athletes
Increased protein metabolism and energy needs
25-100 mg daily
elderly
Reduced absorption and increased requirements
25-50 mg daily
depression-sufferers
Required for serotonin and dopamine synthesis
50-100 mg dailyWhere to buy it
Look for Vitamin B6 (P5P) at 25-100 mg per serving. The form that matters here is Pyridoxal 5'-Phosphate (P5P).
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What else affects it
Beyond other supplements
!
Alcohol
Increases B6 requirements and depletion
Interferes with P5P formation and increases excretionHow it works
- Cofactor for over 100 enzymes in amino acid metabolism
- Required for neurotransmitter synthesis (serotonin, dopamine, GABA)
- Essential for homocysteine metabolism
- Required for hemoglobin synthesis
- Cofactor for glycogen phosphorylase (glucose release)
- Supports immune cell proliferation and antibody production
Key findings
what the evidence supports- Reduces PMS symptoms by 50-70% (multiple RCTs)
- Essential for neurotransmitter synthesis (established biochemistry)
- May reduce cardiovascular risk via homocysteine lowering (JAMA 2006)
- High doses (>200mg) can cause peripheral neuropathy (NEJM 1983)
Sources: NIH Examine.com · data reviewed 2026-08-02
Compiled by Denis, who maintains this database and holds no medical qualification — every figure here is sourced or derived, never asserted. How we calculate it →
Common questions
What are the benefits of Vitamin B6 (P5P)?
Documented effects: Neurotransmitter synthesis; PMS and hormonal support; Amino acid metabolism; Cardiovascular health. Essential for serotonin, dopamine, and GABA production
How much Vitamin B6 (P5P) should you take per day?
The common daily range is 25-100 mg. By goal — maintenance: 10-25 mg; therapeutic: 50-200 mg; maximum: 100 mg (tolerable upper limit); toxic: Above 200 mg daily long-term.
When is the best time to take Vitamin B6 (P5P)?
Morning with food. First effects are typically reported within 1-2 weeks for amino acid metabolism improvements.
What are the side effects of Vitamin B6 (P5P)?
At excessive doses: Peripheral neuropathy (nerve damage), Numbness and tingling in extremities, Loss of muscle coordination, Photosensitivity, Nausea at very high doses. Safety rating at normal doses is 8 out of 10.
What should you not take with Vitamin B6 (P5P)?
Separate it from Alcohol, Pyridoxine Excess by two to four hours. Increases B6 requirements and depletion
Does Vitamin B6 (P5P) interact with medications?
Documented interactions with levodopa, isoniazid-tuberculosis, oral-contraceptives. Discuss these with a pharmacist before combining.
How much Vitamin B6 (P5P) is too much?
The tolerable upper intake level is 100 mg per day for adults, per NIH ODS. Above that, the risk of adverse effects rises: Peripheral neuropathy (nerve damage), Numbness and tingling in extremities, Loss of muscle coordination.
How do you know if you need Vitamin B6 (P5P)?
The marker is Plasma P5P, optimal range 20-121 nmol/L. Common deficiency signs: Depression and irritability, Confusion and cognitive problems, Peripheral neuropathy, Seborrheic dermatitis.