Schilling test for vitamin Bmalabsorption. Feb single large oral doses of vitamin Bare poorly absorbed. The present research evaluates the ability of two different sublingual dosages of . I suggest a dosage just high enough to give you a nice low-average level . The dose of vitamin Brequired varies from individual to individual and working with a doctor or naturopathic doctor to determine the correct dose is . The evidence derived from these limited studies suggests that 20µg doses of oral vitamin Bdaily and 10µg doses initially daily and thereafter weekly . A sensible dosage is a 10to 20microgram tablet taken a few times a week.