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)

Vitamin D is included in most multivitamins, usually in strengths from 50-100 international units (IU). It can be found as softgels, capsules, tablets, and liquids. The new 2010 recommended daily allowance (RDA) is 600 IU for those 1-70 years of age and pregnant or breastfeeding women, and 800 IU for those over 71 years of age. An adequate blood level of vitamin D is 20 nanograms per milliliter, which can be achieved through daily skin exposure to sunlight. Levels over 50 nanograms per milliliter may cause side effects.

For osteomalacia caused by anti-seizure drugs, 2,000 IU of vitamin D2 and 390 milligrams of calcium lactate have been taken by mouth daily for three months.

For atopic eczema, 1,600 IU of cholecalciferol has been taken by mouth alone or with 600 IU man-made all-rac-alpha-tocopherol, daily for 60 days.

For autoimmune diseases, 0.25-2 micrograms of alfacalcidol has been taken by mouth 1-2 times daily and 0.5 micrograms of 1-alfa-OH D3 has been taken by mouth daily for up to 12 months.

For cancer prevention, 400-1,100 IU of vitamin D has been taken by mouth daily, sometimes with 1,400-1,500 milligrams of calcium, for 4-7 years. A dose of 100,000 IU of vitamin D3 has been taken by mouth every four months.

For prostate cancer treatment, 10 micrograms of doxercalciferol has been taken by mouth daily for 28 days. A dose of 45 micrograms of calcitriol (DN-101) has been taken by mouth weekly for three weeks out of every four weeks. Doses of 400-1,100 IU of vitamin D have been taken by mouth daily for 4-7 years.

For heart disease, 200-2,000 IU or 10-25 micrograms of vitamin D2 or D3 has been taken by mouth daily for 1.4-84 months, with or without calcium. A dose of 100,000 IU of vitamin D2 or D3 has been taken by mouth three times yearly for up to three years. A dose of 300,000 IU of vitamin D2 has been injected, followed by doses taken by mouth: 1 gram of vitamin D2, 800 IU of vitamin D3, plus 1 gram of calcium daily for 12 months.

For cognition, 528-9,000 IU of vitamin D2 or D3 has been taken by mouth daily for 8-40 weeks.

For cystic fibrosis, calcitriol, doxercalciferol, or paricalcitol have been taken by mouth. Doses of 800-2,000 IU of vitamin D3 have been taken by mouth daily, which could be increased to a maximum of 10,000 IU daily.

For dental cavities, Vi-delta Liquid emulsion® and Ostelin® have been taken by mouth. A vitamin D mixture in milk has also been used.

For fall prevention, 100-15,000 IU of vitamin D2 or vitamin D3 has been taken by mouth daily, often with calcium for up to 62 months. A dose of 100,000 IU of vitamin D2 has been taken by mouth every three months for up to five years. Single doses of 300,000-500,000 IU have been taken by mouth. Doses of 700-60,000 IU or 0.50 micrograms have been taken by mouth daily or weekly for eight weeks to three years. Doses of 300,000-500,000 IU of vitamin D have been taken yearly without calcium for 1-4 years. A dose of 1 micrograms of alfacalcidol has been taken by mouth daily for 36 weeks and 0.25 micrograms of calcitriol has been taken by mouth daily for three years.

For fertility, 400-50,000 IU of vitamin D has been taken by mouth weekly or every two weeks, alone or with calcium. Elocalcitol has been taken by mouth for three months.

For fibromyalgia, 50,000 IU of vitamin D has been taken by mouth once weekly for three months.

For preventing fractures, 200-1,370 IU or 10-20 micrograms of vitamin D3 has been taken by mouth daily for 7-60 months, with or without calcium (200-1,600 milligrams). Vitamin D has also been taken by mouth in the following forms and doses: 100,000 IU of vitamin D2 every four months for 36 months; 400-5,000 IU daily or twice weekly with calcium; 1 microgram or milligram of alpha-calcidiol daily; 0.25 micrograms of 1 alpha-hydroxyvitamin D daily for six months; and 0.25 milligrams of calcitriol twice daily for two years. A dose of 300,000 IU of vitamin D2 has been injected into the muscle every 12 months for 36 months, or 7,500 micrograms injected into the muscle every 12 months.

For low calcium levels caused by overactive parathyroid glands, 0.5-1 microgram of calcitriol, 0.5 grams of vitamin D, and 400 IU of vitamin D have been taken by mouth 1-2 times daily with 0.5-1.5 grams of calcium carbonate.

For high cholesterol levels, 300-3,332 IU or 7.5-1,250 micrograms have been taken by mouth daily from 42 days to three years and single doses have ranged from 100,000-200,000 IU, in the form of D3 cholecalciferol, calcitriol, ergocalciferol, and alpha-calcidiol, sometimes with calcium (500-1,200 milligrams). Calcitriol has been injected into the vein at a dose of 1 microgram twice weekly for eight weeks.

For high blood pressure, 400-8,571 IU of vitamin D has been taken by mouth daily (with or without calcium), without benefit. A dose of 1,800 IU of vitamin D has been taken by mouth.

For low calcium levels, 0.25 micrograms of calcitriol has been taken by mouth daily, and dosing may be increased by 0.25 micrograms daily at 4-8-week intervals.

For low parathyroid gland activity, dihydrotachysterol has been taken by mouth at an initial dose of 0.75-2.5 milligrams daily for several days. A maintenance dose of 0.2-1 milligram has been taken by mouth daily. Ergocalciferol has been taken by mouth at a dose of 50,000-200,000 IU daily along with four grams of calcium lactate, six times daily.

For immune function, the following doses have been taken by mouth: 40 IU of vitamin D3 daily for 20 years to 100,000 IU of vitamin D3 bimonthly for 12 months, or 10,000 IU daily.

For inflammatory bowel disease, 0.5 micrograms of alfacalcidol has been taken by mouth daily. Cholecalciferol has been taken by mouth in doses of 1,000-1,200 IU daily with 1,200 milligrams of calcium for 12 months.

For chronic kidney disease, 1-9 micrograms of vitamin D has been taken once daily or weekly over a 4-24 week period. Doses of 400-100,000 IU have been taken by mouth daily to monthly for six months to two years. Doses of 0.04-4 micrograms per kilogram of vitamin D have been injected into the vein once or three times weekly over a 4-12 week period.

For mood disorders, 400-800 IU daily or 100,000 IU weekly has been taken by mouth for up to one month to improve symptoms of depression associated with seasonal affective disorder. In obese people, 20,000-40,000 IU of vitamin D has been taken by mouth per week for one year.

For increasing lifespan, 10 micrograms to 400-500,000 IU have been taken by mouth daily for up to 7 years, once every third or fourth month, or once yearly. The following doses have been taken by mouth: cholecalciferol (vitamin D3), 300-1,8000,000 IU; ergocalciferol (vitamin D2), 200-300,000 IU; alfacalcidol (1-alfahydroxy-vitamin D), 1 microgram; and calcitriol (1, 25-dihydroxy-vitamin D), 0.5-2 micrograms, sometimes with 300-1,600 milligrams of calcium, daily to yearly from one day to seven years.

For multiple sclerosis, 10,000 IU has been taken by mouth daily for 12 weeks. Other doses of vitamin D taken by mouth include 5,000 IU daily (in the form of cod liver oil), progressive weekly increases of vitamin D3 (700 micrograms per week, escalating to 7,000 micrograms per week) plus 1,200 milligrams of calcium.

For muscle strength, 20-600,000 IU of ergocalciferol has been taken by mouth or cholecalciferol in doses of 400-150,000 IU, sometimes in combination with 800-1,100 milligrams of calcium, daily for 2-36 months. Vitamin D has been taken by mouth or injected at doses of 400-150,000 IU of D3, 1,000-600,000 IU of D2, and 0.25 micrograms of calcitriol.

For muscle weakness or pain, 100,000 IU of calciferol has been taken by mouth daily for 12 months.

For osteoporosis, 100-200,000 IU of vitamin D2 or D3 have been taken by mouth daily or every two months for six months, sometimes with 800-1,500 milligrams of calcium.

For osteoporosis in people with cystic fibrosis, 0.25 micrograms of calcitrol has been taken by mouth for those under 45 kilograms of weight (0.5 micrograms for those over 45 kilograms) for two years. Doses of 800-1,600 IU have been taken by mouth, with or without 1 gram of calcium for six months.

For osteoporosis caused by drugs, 200-800 IU has been taken by mouth daily, occasionally in combination with calcium (500-1,500 milligrams daily) for up to 24 months.

For parasitic infections, 40 IU of vitamin D has been taken by mouth daily for five days.

For physical performance in elderly subjects, 400 IU of vitamin D plus 800 milligrams of calcium has been taken by mouth daily. In older adults, 8,400 IU of vitamin D3 has been taken by mouth weekly for 16 weeks.

For pregnancy, 400-600,000 IU of vitamin D has been taken by mouth daily from week 12, week 27, or during the third trimester to a single dose (100,000-600,00 0IU) at either the seventh or eighth month of pregnancy. Doses of 400-4000 IU vitamin D have been taken by mouth daily for the third trimester or starting the 12th week of pregnancy; other doses were 120,000-600,000 IU of vitamin D taken by mouth monthly at the 5th, 7th, and/or 8th months or the 27th week of pregnancy.

For the prevention of respiratory tract infections: 400-2,000 IU vitamin D has been taken by mouth daily for up to three years. A dose of 4,000 IU has been taken by mouth daily for one year. An initial dose of 200,000 IU of vitamin D3 has been taken by mouth, followed by 200,000 IU one month later, and 100,000 IU monthly.

For the treatment of respiratory infections, 2,000 IU per kilogram of body weight has been taken by mouth daily for three days.

For rheumatoid arthritis, 50,000 IU of vitamin D has been taken by mouth weekly for 12 weeks.

For tuberculosis, a single dose of 10,000 IU of vitamin D2 has been taken by mouth. Four daily doses of 2.5 milligrams of vitamin D (Viganoil®, Merck Serono) have been taken by mouth on day seven of usual tuberculosis treatment, followed by supplementation on days 14, 28, and 42.

For type 2 diabetes, vitamin D has been taken by mouth in the form of calcitriol, 1-alpha calcidiol, cholecalciferol, doxecalciferol, and ergocalciferol, at doses ranging from 400-200,000 IU, 0.25-2 micrograms, and 1.5 milligrams for seven days to seven years.

For viral infections, 800 IU of vitamin D has been taken by mouth daily for two years, followed by 2,000 IU of vitamin D daily for 12 months.

For deficiency, at least 1,000 IU (25 micrograms) of vitamin D has been taken by mouth daily (or 8,400 IU of vitamin D3 weekly). Other doses that have been studied include 50,000 IU daily for six weeks, 300,000 IU of oral vitamin D3 three times a year, 800 IU daily in combination with calcium, 400 IU daily, and 300,000 IU every three months. 300,000 IU of vitamin D has been used intramuscularly as a bolus dose of vitamin D2 or D3, three times per year, and 600,000 IU (15 milligrams) of vitamin D has been used as a single injection.

For psoriasis, calcipotriene (Dovonex®) has been applied to the skin twice daily. Substances similar to vitamin D have been used alone or with steroids applied to the skin for 3-52 weeks. A dose of 50 milligrams per gram of calcipotriol, 4 milligrams per gram of tacalcitol, and 3 milligrams per gram of calcitriol have been applied to the skin 1-2 times daily for 4-12 weeks.

For senile warts, vitamin D analogs have been applied to the skin in ointments for up to 12 months.

For vitiligo, calcipotriol ointment has been applied to the skin twice daily. Betamethasone dipropionate has been applied to the skin in the morning and calcipotriol in the evening. Calcipotriol or tacalcitol have been used alone or combined with light therapy or steroids applied to the skin twice weekly to twice daily for six weeks to 18 months.

For fall prevention, doses of 300,000-600,000 IU of vitamin D2 have been injected into the muscle once yearly for up to 62 months. The following doses have been used: a single injection into the muscle containing 300,000-600,000 IU of vitamin D or 300,000 IU of vitamin D yearly for three years.

Children (under 18 years old)

The new recommended daily allowance (RDA) is as follows: for those 1-70 years of age, 600 IU daily; and for infants aged 0-12 months, 1,000 IU daily.

For anticonvulsant-induced osteomalacia, 2,000 IU of vitamin D2 has been taken by mouth daily plus 500 milligrams of calcium for three months.

For atopic eczema, 1,600 IU of cholecalciferol, either with or without 600 IU man-made all-rac-alpha-tocopherol, has been taken by mouth daily for 60 days. A dose of 1,000 IU ergocalciferol has been taken by mouth daily for one month.

For cystic fibrosis, 400-10,000 IU of vitamin D has been taken by mouth daily from birth to 12 months.

For immune function, 2,000 IU of vitamin D has been taken by mouth daily during the first year of life.

For osteoporosis (general), 0.25 micrograms of calcitriol has been taken by mouth in combination with 500 milligrams of elemental calcium daily for nine months. Alfacalcidol has been taken by mouth daily for six months.

For osteoporosis (in those with cystic fibrosis), 0.25 micrograms has been taken by mouth for those under 45 kilograms of weight and 0.5 micrograms for those over 45 kilograms, daily for two years. Doses of 800-1,600 IU of vitamin D have been taken by mouth, with or without 1 gram of calcium for six months.

For the prevention of respiratory tract infections, 300-1,200 IU of vitamin D or D3 has been taken by mouth daily for three months to three years, sometimes in milk over three months in winter. A single dose of 100,000 IU vitamin D has been injected into the vein.

For the treatment of respiratory tract infections, a single dose of 100,000 IU of vitamin D3 has been taken by mouth.

Rickets may be treated gradually over several months or in a single day's dose. Based on a clinical trial, a single dose of 600,000 IU of oral vitamin D3 was comparable to a dose of 20,000 IU of oral vitamin D3 daily for 30 days. Gradual dosing may be 125-250 micrograms (5,000-10,000 IU) taken daily for 2-3 months, until recovery is well established and the alkaline phosphatase blood concentration is close to normal limits. Single-day dosing may be 15,000 micrograms (600,000 IU) of vitamin D, taken by mouth divided into 4-6 doses. Injection into the muscle is also an alternative for single-day dosing. For resistant rickets, some authors suggest a higher dose of 12,000 to 500,000 IU daily.

For tuberculosis (TB), 1,000 IU of vitamin D has been taken by mouth in combination with standard TB therapy.

For type 1 diabetes, 2,000 IU of vitamin D taken by mouth daily for a year was associated with a reduced risk of type 1 diabetes.

For viral infection, 60,000 IU has been taken by mouth weekly for six weeks.

For vitamin D deficiency, 2.5 milligrams of vitamin D has been taken by mouth every three months during infancy. A dose of 600,000 IU of cholecalciferol has been taken by mouth.

This evidence-based monograph was prepared by The Natural Standard Research Collaboration

www.naturalstandard.com