If you are currently being treated with any of the following medications, you
should not use vitamin B6 supplements without first talking to your healthcare
Vitamin B6 should not be taken at
the same time as the antibiotic tetracycline because it interferes with the
absorption and effectiveness of this medication. Vitamin B6 either alone or in
combination with other B vitamins should be taken at different times from
tetracycline. (All vitamin B complex supplements act in this way and should
therefore be taken at different times from tetracycline.)
Antidepressant Medications, Tricyclic
Taking vitamin B6
supplements may improve the effectiveness of certain tricyclic antidepressants
such as nortriptyline, especially in elderly individuals. Other tricyclic
antidepressants include desipramine and imipramine.
On the other hand, another class of antidepressants called monoamine oxidase
inhibitors (MAOIs) may reduce blood levels of vitamin B6. Examples of MAOIs
include phenelzine and tranylcypromine.
Preliminary evidence suggest that
pyridoxine may prove useful in treating tardive dyskinesia, a common but
frustrating side effect from medications used to treat schizophrenia. Tardive
dyskinesia is marked by involuntary movements of the mouth and tongue. More
research is needed to know if vitamin B6 can help prevent or treat this side
Anti-tuberculosis medications such as
isoniazid (INH) and cycloserine (used for resistant forms of tuberculosis)
reduce the levels of vitamin B6 in the blood.
Birth control medications
Birth control medications may reduce blood
levels of vitamin B6.
Vitamin B6 may reduce certain side effects of
5-fluorouracil and doxorubicin, two agents used to treat cancer without reducing
the effectiveness of the chemotherapy.
Erythropoietin therapy used for severe anemia
may decrease vitamin B6 levels in red blood cells. Therefore, vitamin B6
supplementation may be necessary during erythropoietin therapy.
Vitamin B6 decreases the effectiveness of
hydralazine, a medication used to treat high blood pressure.
Vitamin B6 reduces the effectiveness of levodopa, a
medication used to treat Parkinson's disease.
People with rheumatoid arthritis taking this
medication often have low levels of vitamin B6.
Penicillamine, a medication used in the
treatment of rheumatoid arthritis and Wilson's disease (excessive amounts of
copper in the body that can lead to liver damage) may decrease levels of vitamin
B6 in the body.
Vitamin B6 reduces the effectiveness of phenytoin, a
medication used to treat seizures.
Long-term treatment with theophylline for asthma
may reduce blood levels of vitamin B6.