Observations on the Mechanism of Intranasal Absorption of Vitamin B₁₂ in Pernicious Anemia

Satisfactory clinical and hematologic response was obtained from the single application to the nasal mucosa of 200 and 150 micrograms of crystalline vitamin B₁₂ in two patients with pernicious anemia.

Thirty-two patients with pernicious anemia in relapse and 55 in remission have been controlled satisfactorily by intranasal B₁₂ either in saline solution, lactose powder, or as crystals. Absorption of the vitamin was probably direct and did not require binding with "intrinsic substance." Chronic disease of the nose did not contraindicate this modality of therapy; local irritation of the mucous membranes by the crystalline B₁₂ or the vehicles employed has not been observed.