Vitamin B6 (Pyridoxine HCl)

Most common and researched form of vitamin B6, requiring conversion to active P5P form in the body

Scientific namePyridoxine Hydrochloride FormulaC8H11NO3·HCl Molecular weight205.64 g/mol CAS58-56-0

75 absorption score

8 safety / 10

8 USD per month

5 documented interactions

Check it against something

Evidence level A

Vitamin B6 (Pyridoxine HCl) with:

99 out of 100

Works better together Compatible. Timing differs, so follow each supplement's own window.

Check it against your whole stack →

What it does

mechanism and evidence for each claim

Neurotransmitter synthesis

Essential for serotonin, dopamine, and GABA production

Converted to P5P cofactor for decarboxylase enzymes Evidence A-grade 2-4 weeks

PMS and hormonal support

May reduce PMS symptoms by 50-70%

Supports dopamine synthesis and hormone metabolism Evidence A-grade 2-3 menstrual cycles

Amino acid metabolism

Essential for protein utilization and muscle building

Converted to P5P for transaminase enzyme function Evidence A-grade 1-2 weeks

Morning sickness relief

Reduces nausea and vomiting in pregnancy

Unknown, possibly neurotransmitter modulation Evidence A-grade 1-2 weeks

Cardiovascular health

Helps maintain healthy homocysteine levels

Required for homocysteine to cysteine conversion Evidence A-grade 4-8 weeks

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 (Pyridoxine HCl) + Caffeine No documented interaction either way No known interaction 70

Vitamin B6 (Pyridoxine HCl) + Creatine Monohydrate No documented interaction either way No known interaction 70

Vitamin B6 (Pyridoxine HCl) + Whey Protein No documented interaction either way No known interaction 70

Vitamin B6 (Pyridoxine HCl) + Turmeric No documented interaction either way No known interaction 70

Vitamin B6 (Pyridoxine HCl) + Lactase Improved calcium absorption when consuming dairy Works better together 82

Vitamin B6 (Pyridoxine HCl) + Bovine Collagen Essential for collagen synthesis and cross-linking Works better together 82

Vitamin B6 (Pyridoxine HCl) + DHA Prevents oxidation of DHA and enhances stability Works better together 82

Vitamin B6 (Pyridoxine HCl) + Vitamin D3 Required for B6 metabolism and activation Works better together 90

Vitamin B6 (Pyridoxine HCl) + Fish Oil (EPA/DHA) Protects fish oil from oxidation Works better together 90

Vitamin B6 (Pyridoxine HCl) + Magnesium Oxide Required for pyridoxine conversion to P5P Works better together 94

Vitamin B6 (Pyridoxine HCl) + Calcium Carbonate Essential for calcium absorption and utilization Works better together 94

Vitamin B6 (Pyridoxine HCl) + Zinc Gluconate Works together in amino acid metabolism Works better together 99

Dosage

Morning with food

Daily25-100 mg

Maintenance10-25 mg

Therapeutic50-200 mg

Maximum100 mg (tolerable upper limit)

Pregnancy nausea25-50 mg

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

$80-120

MarkerPlasma pyridoxal phosphate (PLP/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 suspect

Most reported effects

Neuropathy peripheral 34

Paraesthesia 16

Hypoaesthesia 15

Hypervitaminosis 12

Anxiety 11

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 High 75 of 100 · absorbs well relative to other forms

Delivered daily 46.9 mg

Cost per 100 mg delivered $0.57 comparative — uses the absorption score, not a measured percentage

Works better with

3 documented

Magnesium

Required for pyridoxine conversion to P5P

Cofactor for pyridoxal kinase enzyme · 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 pyridoxine phosphate oxidase · level A

What not to take with Vitamin B6 (Pyridoxine HCl)

2 documented

Alcohol

Increases B6 requirements and impairs conversion

Interferes with P5P formation and increases excretion · moderate significance

P5p At High Doses

Theoretical competition between forms

May compete for transport and enzyme binding · controversial significance

Medication interactions

Discuss these with a pharmacist before combining

levodopa Major

B6 may reduce levodopa effectiveness

What to do: Avoid B6 supplements or use carbidopa combination

isoniazid-tuberculosis Major

Isoniazid depletes B6 and may cause neuropathy

What to do: Prophylactic B6 supplementation recommended

oral-contraceptives Moderate

Birth control pills deplete B6 levels

What to do: Consider B6 supplementation

Available forms

bioavailability compared

Pyridoxine HCl 75

Pyridoxine HCl: Most research, Least expensive, Very stable, FDA-approved uses

Food sources

before you supplement

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

Bananas 0.4 mg/100g · 70

Too little

deficiency signs

Depression and irritability
Confusion and cognitive problems
Peripheral neuropathy
Seborrheic dermatitis
Anemia (microcytic)
Weakened immune function
Increased PMS symptoms

Too much

toxicity signs

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

pregnant-women-morning-sickness

FDA-approved for nausea and vomiting in pregnancy

25-50 mg daily

women-with-pms

Extensive research shows B6 reduces PMS symptoms

50-100 mg daily

budget-conscious

Most cost-effective form of vitamin B6

25-100 mg daily

birth-control-users

Oral contraceptives deplete B6 levels

25-50 mg daily

athletes

Increased protein metabolism needs

25-100 mg daily

Where to buy it

compare forms first

Look for Vitamin B6 (Pyridoxine HCl) at 25-100 mg per serving. The form that matters here is Pyridoxine HCl.

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What else affects it

Beyond other supplements

Alcohol

Increases B6 requirements and impairs conversion

Interferes with P5P formation and increases excretion

How it works

Converted to P5P by pyridoxal kinase enzyme
P5P serves as cofactor for 100+ enzymes
Required for neurotransmitter synthesis
Essential for amino acid metabolism
Needed for hemoglobin synthesis
Required for immune function

Key findings

what the evidence supports

Reduces PMS symptoms by 50-70% (multiple RCTs)
FDA-approved for morning sickness treatment
Essential for neurotransmitter synthesis (established biochemistry)
Most studied form with decades of safety data

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 (Pyridoxine HCl)?

Documented effects: Neurotransmitter synthesis; PMS and hormonal support; Amino acid metabolism; Morning sickness relief. Essential for serotonin, dopamine, and GABA production

How much Vitamin B6 (Pyridoxine HCl) 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); pregnancy nausea: 25-50 mg.

When is the best time to take Vitamin B6 (Pyridoxine HCl)?

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 (Pyridoxine HCl)?

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 (Pyridoxine HCl)?

Separate it from Alcohol, P5p At High Doses by two to four hours. Increases B6 requirements and impairs conversion

Does Vitamin B6 (Pyridoxine HCl) interact with medications?

Documented interactions with levodopa, isoniazid-tuberculosis, oral-contraceptives. Discuss these with a pharmacist before combining.

How much Vitamin B6 (Pyridoxine HCl) 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 (Pyridoxine HCl)?

The marker is Plasma pyridoxal phosphate (PLP/P5P), optimal range 20-121 nmol/L. Common deficiency signs: Depression and irritability, Confusion and cognitive problems, Peripheral neuropathy, Seborrheic dermatitis.

Taken for

52 Brain & Focus

Caffeine · DHA · Fish Oil (EPA/DHA)

27 Hormones

Melatonin · Vitamin B6 (Pyridoxine HCl) · Vitamin B6 (P5P)