pyridoxine (a vitamin B6)

^[1]^[2]^[3]^[4]^[5]^[6]^[7]

Introduction

(see also pyridoxal & pyridoxamine)

Function

derivatives are cofactors in:

aminotransferases
many intermediary reactions
- amino acid metabolism
- phospholipid metabolism
- glycogen metabolism

Indications

B vitamin, prevention of pyridoxine deficiency
prophylaxis against peripheral neuropathy induced by isoniazid
homocysteinemia
- homocystinuria
- cystathioninuria^[5]
GABA AT deficiency
hyperoxaluria^[5]
sideroblastic anemia
nausea/vomiting
seizures^[5]
may improve generalized anxiety, social anxiety & visual processing*^[7]

* increased surround suppression of visual contrast detection^[7]

Dosage

RDA: male: 1.7-2 mg; female: 1.4-1.6 mg
isoniazid prophylaxis: 25-50 mg PO QD
anxiety & increased surround suppression of visual contrast detection: 100 mg/day^[7]

Adverse effects

pyridoxine neuropathy (2-3 g/day, +/- reversible)
- as little as 200 mg/day chronically is neurotoxic^[2]
- 500 mg/day is safe^[3]
unstable gait
somnolence
supplementation of folic acid 0.8 mg, vit B12 0.4 mg & vit B6 40 mg QD
- increases risk of cancer
- increases risk of dying of cancer
- increases all cause mortality
- hazzard ratio 1.2-1.4, number needed to harm 40-90^[4]
- increases mainly driven by folic acid + vitamin B12
- vitamin B6 not associated with any significant effects
- editorialist proposes folic acid as culprit
vitamin B6 > 20 mg/day associated with increased risk of lung cancer in men^[2]

Drug interactions

decrease in L-dopa effectiveness by increasing peripheral metabolism
high doses of both vit B6 & vit B12 associated with 50% higher risk of high fracture in postmenopausal women^[6]

More general terms

More specific terms

4-pyridoxate; 4-pyridoxic acid; 4-pyridoxinic acid; 4-pyridoxylic acid; 3-hydroxy-5-(hydroxymethyl)-2-methylpyridine-4-carboxylate

Additional terms

Component of

References

↑ Drug Information & Medication Formulary, Veterans Affairs, Central California Health Care System, 1st ed., Ravnan et al eds, 1998 Department of Veterans Affairs, VA National Formulary
↑ ^2.0 ^2.1 ^2.2 Brasky TM, White E, Chen CL. Long-Term, Supplemental, One-Carbon Metabolism-Related Vitamin B Use in Relation to Lung Cancer Risk in the Vitamins and Lifestyle (VITAL) Cohort. J Clin Oncol. 2017 Aug 22:JCO2017727735. PMID: https://www.ncbi.nlm.nih.gov/pubmed/28829668
↑ ^3.0 ^3.1 Harrison's Principles of Internal Medicine, 14th ed. Fauci et al (eds), McGraw-Hill Inc. NY, 1998, pg 2200
↑ ^4.0 ^4.1 Ebbing M et al Cancer incidence and mortality after treatment with folic acid and vitamin B12. JAMA 2009 Nov 18; 302:2119. PMID: https://www.ncbi.nlm.nih.gov/pubmed/19920236
Drake BF and Colditz GA Assessing cancer prevention studies - A matter of time. JAMA 2009 Nov 18; 302:2152 PMID: https://www.ncbi.nlm.nih.gov/pubmed/19920243
↑ ^5.0 ^5.1 ^5.2 ^5.3 Deprecated Reference
↑ ^6.0 ^6.1 Meyer HE, Willett WC, Fung TT, Holvik K, Feskanich D. Association of high intakes of vitamins B6 and B12 from food and supplements with risk of hip fracture among postmenopausal women in the Nurses' Health Study. JAMA Netw Open 2019 May 3; 2:e193591. PMID: https://www.ncbi.nlm.nih.gov/pubmed/31074816 https://jamanetwork.com/journals/jamanetworkopen/fullarticle/2733176
↑ ^7.0 ^7.1 ^7.2 ^7.3 Field DT, Cracknell RO, Eastwood JR et al High-dose Vitamin B6 supplementation reduces anxiety and strengthens visual surround suppression. Human Psychopharmacology: Clinical & Experimental. 2022 July 19:e2852 PMID: https://www.ncbi.nlm.nih.gov/pubmed/35851507 https://onlinelibrary.wiley.com/doi/10.1002/hup.2852

Database

Kegg: http://www.genome.jp/dbget-bin/www_bget?
PubChem: http://pubchem.ncbi.nlm.nih.gov/summary/summary.cgi?cid=1054

[ref1-1] Drug Information & Medication Formulary, Veterans Affairs, Central California Health Care System, 1st ed., Ravnan et al eds, 1998 Department of Veterans Affairs, VA National Formulary

[ref2-2] 2.0 ^2.1 ^2.2 Brasky TM, White E, Chen CL. Long-Term, Supplemental, One-Carbon Metabolism-Related Vitamin B Use in Relation to Lung Cancer Risk in the Vitamins and Lifestyle (VITAL) Cohort. J Clin Oncol. 2017 Aug 22:JCO2017727735. PMID: https://www.ncbi.nlm.nih.gov/pubmed/28829668

[ref3-3] 3.0 ^3.1 Harrison's Principles of Internal Medicine, 14th ed. Fauci et al (eds), McGraw-Hill Inc. NY, 1998, pg 2200

[ref4-4] 4.0 ^4.1 Ebbing M et al Cancer incidence and mortality after treatment with folic acid and vitamin B12. JAMA 2009 Nov 18; 302:2119. PMID: https://www.ncbi.nlm.nih.gov/pubmed/19920236
Drake BF and Colditz GA Assessing cancer prevention studies - A matter of time. JAMA 2009 Nov 18; 302:2152 PMID: https://www.ncbi.nlm.nih.gov/pubmed/19920243

[ref5-5] 5.0 ^5.1 ^5.2 ^5.3 Deprecated Reference

[ref6-6] 6.0 ^6.1 Meyer HE, Willett WC, Fung TT, Holvik K, Feskanich D. Association of high intakes of vitamins B6 and B12 from food and supplements with risk of hip fracture among postmenopausal women in the Nurses' Health Study. JAMA Netw Open 2019 May 3; 2:e193591. PMID: https://www.ncbi.nlm.nih.gov/pubmed/31074816 https://jamanetwork.com/journals/jamanetworkopen/fullarticle/2733176

[ref7-7] 7.0 ^7.1 ^7.2 ^7.3 Field DT, Cracknell RO, Eastwood JR et al High-dose Vitamin B6 supplementation reduces anxiety and strengthens visual surround suppression. Human Psychopharmacology: Clinical & Experimental. 2022 July 19:e2852 PMID: https://www.ncbi.nlm.nih.gov/pubmed/35851507 https://onlinelibrary.wiley.com/doi/10.1002/hup.2852

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pyridoxine (a vitamin B6)

Contents

Introduction

Function

Indications

Dosage

Adverse effects

Drug interactions

More general terms

More specific terms

Additional terms

Component of

References

Database

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pyridoxine (a vitamin B6)

Introduction

Function

Indications

Dosage

Adverse effects

Drug interactions

More general terms

More specific terms

Additional terms

Component of

References

Database

Navigation menu

Search