Efficacy of different routes of vitamin B12 supplementation for the treatment of patients with vitamin B12 deficiency: A systematic review and network meta analysis Irish Journal of Medical Science (1971 ) These highlights do not include all the information needed to use NASCOBAL NASAL SPRAY safely and effectively. See full prescribing information for NASCOBAL NASAL SPRAY. NASCOBAL (cyanocobalamin nasal spray)Initial U.S. Approval: 1942 The Normal Mechanisms & Defects of Absorption of Vitamin B12.The vitamin B12(Cbl) released from food protein by peptic action is bound to haptocorrin(HC)in the stomach &travels to the duodenum,where pancreatic proteases digest B12 Methylcobalamin vs Hydroxocobalamin The difference between in clinic B12 injections vs over the counter. There are many forms of vitamin B12, the form used at La Bella is Methylcobalamin. The