Academy of Medical Sciences of I.R. Iran Archives of Iranian Medicine 1029-2977 26 10 2023 10 01 Anti-N-methyl D-aspartate Receptor Encephalitis Following ChAdOx1 nCoV-19 Vaccination: A Case Report 600 603 10.34172/aim.2023.87 EN Zahra Liyaghatdar https://orcid.org/0000-0002-8804-5179 Amirhosein Rahimkhani Amin Liaghatdar https://orcid.org/0000-0002-1407-7071 Journal Article 10.34172/aim.2023.87 2023 04 05 2023 07 03 As of December 2020, millions of people have been immunized using vaccines against SARS-CoV-2. A wide range of neurological adverse effects of SARS-CoV-2 vaccines have been reported so far. Here, we report a 23-year-old male who experienced psychiatric symptoms, loss of consciousness, language disintegration, and incontinency that happened 10 days after the first dosage of the COVID-19 AstraZeneca vaccine. Anti-NMDAR Encephalitis was diagnosed based on the results of the autoimmune panel. The patient responded to intravenous dexamethasone very well and experienced no other complications in 6 months of follow-up. Scientific reports of neurological side effects such as anti-NMDAR encephalitis after vaccination are necessary to optimize the safety and effectiveness of SARS-CoV-2 vaccines.