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Dosing

The below doses are based on scientific research, publications, traditional use, or expert opinion. Many herbs and supplements have not been thoroughly tested, and safety and effectiveness may not be proven. Brands may be made differently, with variable ingredients, even within the same brand. The below doses may not apply to all products. You should read product labels, and discuss doses with a qualified healthcare provider before starting therapy.

Adults (18 years and older)

Recommended dietary allowances (RDAs) of vitamin B6 by mouth daily are as follows: for males 19-50 years old, 1.3 milligrams; for males 51 years old and older, 1.7 milligrams; for females 19-50 years old, 1.3 milligrams; and for females 51 years old and older, 1.5 milligrams. Some researchers think the RDA should be increased to the following daily: for women 19-50 years old, 1.5-1.7 milligrams; for pregnant women, 1.9 milligrams; and for lactating women, two milligrams.

Recommended maximum daily intake of vitamin B6 by mouth for adults, pregnant, and lactating women (over 18 years old) is 100 milligrams. A doctor and pharmacist should be consulted for dosing in other conditions.

For anemia, 25 milligrams of vitamin B6 has been taken by mouth in combination with multivitamins from the second trimester to delivery in pregnant HIV-positive women.

For anxiety, 50 milligrams of vitamin B6 has been taken by mouth in combination with magnesium daily.

For birth outcomes, the following doses have been taken by mouth: 20 milligrams daily; three lozenges daily with 6.67 milligrams of pyridoxine in each lozenge; 2.6-20 milligrams of pyridoxine HCl daily; 25 milligrams of pyridoxine HCl daily; and a single dose of 100 milligrams.

For carpal tunnel syndrome, 200 milligrams of vitamin B6 has been taken by mouth daily for 10-12 weeks.

For cognitive function, 20 milligrams of vitamin B6 has been taken by mouth daily for 12 weeks.

For dysmenorrhea, 200 milligrams of vitamin B6 has been taken by mouth daily.

For gestational diabetes, 100 milligrams of vitamin B6 has been taken by mouth daily for 14 days.

For high blood pressure, five milligrams of vitamin B6 per kilogram of body weight has been taken by mouth daily for four weeks.

For McArdle's disease, 50 milligrams of vitamin B6 has been taken by mouth daily for 10 weeks, without evidence of benefit.

For pregnancy-induced nausea and vomiting, the following doses have been taken by mouth: 25 milligrams of vitamin B6 every eight hours for 72 hours; 10 milligrams pyridoxine HCl every eight hours for five days; and 100 milligrams of vitamin B6 daily for seven days.

For premenstrual syndrome, up to 600 milligrams has been taken by mouth; however, 100 milligrams daily has been suggested as the optimal level, due to the potential for side effects at higher doses.

Children (under 18 years old)

The recommended dietary allowances (RDAs) of vitamin B6 (daily) are as follows: for infants 0-6 months old, 0.1 milligrams; for infants 7-12 months old, 0.3 milligrams; for children 1-3 years old, 0.5 milligrams; for children 4-8 years old, 0.6 milligrams; for children 9-13 years old, one milligram; for males 14-18 years old, one milligram; and for females 14-18 years old, 1.2 milligrams.

The recommended maximum daily intakes of vitamin B6 are as follows: for children 1-3 years old, 30 milligrams; for children 4-8 years old, 40 milligrams; for children 9-13 years old, 60 milligrams; and for adult males and females, and pregnant and lactating females 14-18 years old, 80 milligrams.

For hereditary sideroblastic anemia, 2-25 milligrams of vitamin B6, alone or in combination with iron or a multivitamin has been taken by mouth for up to eight weeks.

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