Sozer, KubraGorgulu, YaseminSonmez, Mehmet BulentCinar, Rugul Kose2024-06-122024-06-1220191018-86811309-5749https://doi.org/10.14744/DAJPNS.2019.00009https://search.trdizin.gov.tr/yayin/detay/323805https://hdl.handle.net/20.500.14551/21291While obesity surgery can improve obesity and its complications, it may decrease the absorption of some foods in the stomach. It is known that from the first day after gastric bypass operation, the blood level of B12 start to decrease. However, the change of B12 levels can be measurable after 6 months. B12 deficiency may cause several psychiatric and neurological disorders or aggravate psychiatric symptoms. In this case report, we present a patient who had been in remission before gastric surgery but developed major depression with psychotic features and to describe the course of treatment.en10.14744/DAJPNS.2019.00009info:eu-repo/semantics/openAccessGastric BypassPsychotic DepressionVitamin B12 ReplacementGastric BypassDiagnosisArticle3216568N/AWOS:0004627318000092-s2.0-85064592660Q3323805