Individuals experiencing Lewy body disease (LBD) are particularly vulnerable to the adverse effects of neuroleptics. This sensitivity has been employed by some authorities as a diagnostic component for this disorder. At present, we do not have any Food and Drug Administration-approved antipsychotic for the management of psychotic symptoms in this condition. We present the first case of an LBD patient, showing favorable response in psychotic symptoms with lumateperone, a novel atypical neuroleptic. Our report revealed improvements in cognition, psychosis, and sleep following the initiation of lumateperone without concurrent emergence of extrapyramidal side effects, autonomic instability, parkinsonian features, or cognitive decline, which are typically seen when treated with available antipsychotic medications. Clinicians may wish to consider potential usefulness of lumateperone when managing patients with this disabling condition. (PsycInfo Database Record (c) 2024 APA, all rights reserved).