Management of Psychotic Symptoms in a Patient With Parkinson's Disease Maintained on Levodopa-Carbidopa Intestinal Gel by Paliperidone Long-Acting Injection: A Case Report.

This case presents a 47-year-old man, without known past psychiatric history who developed psychotic symptoms including delusions of infidelity and had homicidal plans against his wife after 10 months of Levodopa-Carbidopa intestinal gel insertion (LCIG). The patient was diagnosed with Parkinson's disease at age 34, which is being managed with LCIG. Patient Parkinson's symptoms were not well controlled with other pharmacological and surgical interventions tried previously. Despite the current guidelines in treating Parkinson's disease psychosis, the treating teams have faced many difficulties with the management of this patient's psychotic symptoms. After trying Risperidone Consta on August 24, 2018, the patient improved gradually, then he was shifted to Paliperidone long-acting injection (LAI) on September 12, 2018. One month later, the patient was seen in the outpatient department with much improvement in Paliperidone LAI. Reporting this case as the patient was seen on November 29, 2021, the patient is stable and doing well overall in terms of absent psychotic symptoms with minimal resting tremors. The success story of using LAIs such as our patient's response to Paliperidone LAI can help other psychiatrists expand their treatment options when facing such difficulties.