Fluphenazine-Induced Neurotoxicity with Acute Almost Transient Parkinsonism and Permanent Memory Loss: Lessons from a Case Report

We report the singular case of a 31-year-old woman who developed very serious Fluphenazine-induced parkinsonism over a few days due to a doubly incongruent drug prescription by indication and dosage having been applied to a healthy subject over one week instead of seven months. Unlike gradual drug-induced parkinsonism, our patient experienced acute extrapyramidal syndrome (EPS), reaching significant motor and sphincter disability in just a few days, followed by a gradual incomplete recovery over more than six months. In fact, after drug discontinuation, hypomimia and slight left hemi-somatic rigidity with bradykinesia remained, as well as stable non-progressive memory disturbances. Despite bio-humoral and instrumental investigations and DaTScan were negative, MRI post-analysis evidenced a 6.5% loss in brain volume. Specifically, irreversible cortical and sub-cortical grey matter reduction and cerebrospinal fluid space enlargement with spared white matter were found. Our observations suggest that the sudden availability of Fluphenazine results in a kind of plateau effect of parkinsonism presentation, partially reversible due to the neurotoxic drug effect on the cortical and sub-cortical grey matter, resulting in asymmetric EPS and stable memory loss, respectively. Our report confirms the debated neurotoxicity of first-generation neuroleptics and the postulated theory of differential susceptibility to the cytotoxic stressors on the central nervous system.