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)

The recommended daily intake of vitamin B6 is as follows: 1.3 milligrams in men and women ages 19-50; 1.7 milligrams in men aged 51 and older; and 1.3 milligrams in women aged 51 and older. The maximum daily intake of vitamin B6 in adults and pregnant or breastfeeding women over age 18 is 100 milligrams.

For anemia, 25 milligrams of vitamin B6 has been taken by mouth with multivitamins.

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

For birth outcomes, the following doses of vitamin B6 have been taken by mouth: three lozenges daily, each containing 6.67 milligrams of pyridoxine; 6.67-20 milligrams of pyridoxine daily; 1-25 milligrams of pyridoxine HCl daily; and a single dose of 100 milligrams. A dose of 100 milligrams of pyridoxinum hydrochloricum has been injected into the muscle.

For heart disease (high homocysteine levels), 40 milligrams of vitamin B6 has been taken by mouth daily.

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 menstrual cramps, 200 milligrams of vitamin B6 has been taken by mouth daily.

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

For high blood pressure, 5 milligrams of vitamin B6 per kilogram of body weight has been taken by mouth daily for four weeks.

For reducing breast milk, 200 milligrams of pyridoxine has been taken by mouth 2-3 times daily for 6-7 days.

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

For nerve pain, 6 milligrams of vitamin B6 has been taken by mouth daily.

For nausea and vomiting of pregnancy, the following doses of vitamin B6 have been taken by mouth: 25 milligrams every eight hours for 72 hours; 10 milligrams of pyridoxine HCl every eight hours for five days; and 100 milligrams daily for seven days. Doses of 30-100 milligrams of pyridoxine have been taken by mouth in 1-3 divided doses daily for three days to three weeks.

For premenstrual syndrome (PMS), up to 600 milligrams of vitamin B6 has been taken by mouth, with 100 milligrams daily suggested as the optimal level.

Children (under 18 years old)

The recommended daily intake of vitamin B6 is as follows: 0.1 milligrams for babies aged 0-6 months; 0.3 milligrams for babies aged 7-12 months; 0.5 milligrams for children aged 1-3 years; 0.6 milligrams for children aged 4-8 years; 1 milligram for children aged 9-13 years; 1 milligram for males aged 14-18 years; and 1.2 milligrams for females aged 14-18 years. The maximum daily intake of vitamin B6 is 30 milligrams for children aged 1-3 years, 40 milligrams for children aged 4-8 years, 60 milligrams for children aged 9-13 years, and 80 milligrams for adult males and females and pregnant or breastfeeding females aged 14-18 years.

For atopic eczema (skin disorder causing itchy, scaly rashes) in children over 12 months of age, 50 milligrams of pyridoxine hydrochloride has been taken by mouth for four weeks.

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

For seizures caused by fever, 20 milligrams of pyridoxine has been taken by mouth twice daily for 12 months.

Although no relationship has been found between B6 status and the incidence of morning sickness, using 10–40 mg/day appears to reduce the severity of NVP symptoms.  B6 dose can be adjusted according to maternal weight and severity of NVP, and maternal doses of up to 500 mg/day can be used without  increasing maternal adverse effect or jeopardizing fetal safety. However, a dose of up to 200 mg/day, as suggested in the 2007 Motherisk NVP algorithm, is the current  recommended high dose. Concerns about maternal toxicity have been reported with dosages much higher  than 500 mg/day, and in the 2000–6000 mg/day range.

References

1. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2990891/

2. https://www.nps.org.au/australian-prescriber/articles/treatment-of-nausea-and-vomiting-in-pregnancy

As stated in a previous response, there does not seem to be any direct relationship between emesis gravidarum and the serum B6 levels. However, in my practice the addition of parenteral B6 injections to intravenous infusions in managing hyperemesis gravidarum has been found to help. For 'normal' vomiting in pregnancy, an oral dose of between 50-100mg daily has been found to be adequate.

Up to 90-100 mg per day.