Phelan-McDermid syndrome (PMS) is a rare neurodevelopmental disease, caused by an autosomal dominant mutation due to the terminal deletion of 22q13, leading to a defect in the SHANK3 protein. We present the clinical case of a 12-year-old patient with this syndrome, who underwent three interventions that required general anesthesia. In none of them did she present intraoperative or postoperative complications.