Vitamin B12 is found in many foods. Generally, when there is deficiency, it is due to a problem with absorption. For that reason, vitamin B12 deficiency is generally treated with injections. But it turns out that if the dosage is high enough, vitamin B12 can be taken orally. A review of research appearing in Family Practice News (November 15, 2004:59) shows that taking vitamin B12 orally may be as effective as getting by injection. The article reviewed four earlier studies that compared oral B12 supplementation with injections and placebos in patients with documented B12 deficiency. The studies showed taking a high dose orally (between one and two milligrams per day) is as effective as B12 injections. Lower doses were not as effective, in fact at 10 mcg per day, oral B12 supplementation is no more effective than placebo. Doctors in Sweden use oral B12 therapy instead of injections and have been getting good results for over 30 years.