Abstract Disclosure: L.D. Santos: None. G. Oliveira Martins: None. L. Costa Figueiredo: None. M. Nascimento de Lemos: None. J.V. Lima: None. L.A. Alvares: None. E.N. Sakane: None. N. Scalissi: None. Post-surgical hypoparathyroidism is an event that may occur, especially after extensive procedures in the cervical region. There are few long-term follow-up studies on individuals who develop permanent post-surgical hypoparathyroidism and its long-term complications. Objective: This study aims to assess the clinical and laboratory characteristics of patients diagnosed with permanent hypoparathyroidism at a tertiary care center in Brazil. Methods: We conducted a retrospective analysis of medical records. Results: We evaluated 27 patients with permanent hypoparathyroidism, with an average age of 53 years (SD=10), where 15% were alcohol and tobacco consumers, and 88% were female. The average time of permanent hypoparathyroidism diagnosis was 9 years and 3 months. Regarding the surgical indication, 35% were due to Graves' disease, 25% for thyroid goiter, 25% for thyroid cancer, and 15% for glottic cancer. Only 15% had a description of the parathyroid glands in the pathology report. As for medications, all patients were using calcium carbonate, with an average dose of 1700 mg daily per individual. 90% of the patients were using calcitriol, with an average dose of 0.64 mcg daily, and 55% were using cholecalciferol, with an average weekly dose of 9700 IU. Hydrochlorothiazide was used by 35% of the patients, with an average daily dose of 34 mg. Regarding postoperative exams 24 hours after surgery, only half had the parathyroid hormone (PTH) test requested or available, with only one patient having PTH >10 pg/mL. Regarding chronic complications, 15% presented with nephrolithiasis, 5% with subcapsular cataract, 5% with prophylaxis for seizures, 15% with a diagnosis of depression, and 10% with arrhythmias. Conclusion: Individuals with permanent hypoparathyroidism require attention due to chronic complications, and proper treatment aims to reduce the chance of developing other diseases associated with permanent post-surgical hypoparathyroidism. Presentation: 6/2/2024