Vitamin B12, cyanocobalamin, is implicated in metabolic and neurotrophic functions. Its deficiency is associated with hematological, neurological and psychiatric disorders. Herein we report the case of a patient presenting with refractory depression who improved after the identification and treatment of vitamin B12 deficiency. This report highlights the relevance of considering secondary causes of depression in refractory cases.
Depression; vitamin B12; treatment; refractoriness