23 Supplementation of 1 mg daily is recommended for patients with specific risk factors (e.g., bariatric/gastric surgery patients, those with severe malnutrition, chronic alcohol use, chronic hemolytic anemia and conditions with high cell turnover, and use of antimetabolite medications such as methotrexate)
For a solution delivering 250mcg per spray, a common research protocol might involve one spray in one nostril in the morning and one spray in the other nostril in the evening
Journal of dietary supplements
Lincoff AM, Brown-Frandsen K, Colhoun HM, Deanfield J, Emerson SS, Esbjerg S, Hardt-Lindberg S, Hovingh GK, Kahn SE, Kushner RF, Lingvay I, Oral TK, Michelsen MM, Plutzky J, Torne CW, Ryan DH
[27] Additionally, anyone with Lebers hereditary optic neuropathy (a rare inherited eye disease) must avoid cyanocobalamin injections, since B can precipitate rapid worsening of that condition
These may include: Dietary changes: Certain foods and drinks are known to worsen symptoms in some individuals